Showing papers in "European Heart Journal in 1988"
TL;DR: TOE seems to be indicated in patients with suspected endocarditis and reduced image quality or negative TTE results, and early detection of vegetations on valves may help confirm the diagnosis of infectiveendocarditis at an early stage and hopefully lead to an improved prognosis by reducing delay in instituting appropriate therapy.
Abstract: In a prospective study, the clinical value of transoesophageal two-dimensional echocardiography (TOE) as compared with transthoracic two-dimensional echocardiography (TTE) was determined in patients with suspected infective endocarditis. Ninety-six patients were studied consecutively with an electronic sector scanner using 2–25 and 3–5 MHz probes for TTE and a 3–5 MHz probe embedded in the tip ofaflexible 12 mm gastroscope for TOE.
Results of surgery and autopsy were available for 20 of the 96 patients with infective endocarditis and echocardiographically demonstrated vegetations and 70 control patients with valvular heart disease without infective endocarditis and no signs of vegetations, who were studiedpreoperatively with TTE and TOE. For TTE and TOE, the measured sensitivity was 63% and 100%, specificity 98% and 98%, positive predictive accuracy 92% and 95%, and negative predictive accuracy 91% and 100%, respectively. In 39 patients who had positive blood cultures, vegetations were found by TOE in 32 patients (82%), but in only 27 patients (69%) by TTE. Image quality was the main factor contributing to the superiority of TOE over TTE: it was reduced in 11/20 patients (55%) in whom vegetations were not detected by TTE. Another important factor was the size of vegetations. Only 6/24 vegetations (25%) of 11 mm detected by TOE were also observed with TTE. The clinical importance of detecting vegetations was demonstrated by the rate of embolism. In patients with vegetations embolism was 25% when blood cultures were positive and 21% when they were negative. In patients without echocardiographically detectable vegetations signs of embolism were seen in no patient with positive and 7% of the patients with negative blood cultures. Evidence of vegetations was found on the aortic valve in 14 patients and on the mitral valve in seven patients in whom valvular incompetence was not present, indicating that the valve had not yet been damaged significantly.
TOE is superior to TTE in detecting vegetations in suspected infective endocarditis because of better image quality, particularly when vegetations are small. TOE seems to be indicated in patients with suspected endocarditis and reduced image quality or negative TTE results. Early detection of vegetations on valves may help confirm the diagnosis of infective endocarditis at an early stage and hopefully lead to an improved prognosis by reducing delay in instituting appropriate therapy.
411 citations
TL;DR: Despite different aetiologies, acquired aortic stenosis is a self-maintaining, slowly progressive process with good long-term prognosis, and there was clinical progression within 10 years of the initial diagnosis in only 12% of patients.
Abstract: Despite different aetiologies, acquired aortic stenosis is a self-maintaining, slowly progressive process with good long-term prognosis. In 142 patients with mild stenosis, there was clinical progression within 10 years of the initial diagnosis in only 12% of patients. Twenty-five years after the diagnosis had been established, the severity of aortic stenosis was clinically unchanged in 38%, while 25% of patients had moderate stenosis and 35% had undergone valve replacement. Progression of moderate aortic stenosis was more rapid: the average time interval between the manifestation of moderate aortic stenosis and surgery was 13.4 years. Age at the onset of initial symptoms was related to aetiology: 39 +/- 18 years with rheumatic aortic stenoses, 48 +/- 6 years in patients with bicuspid valves who had no history of rheumatic fever, infective endocarditis or myocarditis, and 66 +/- 12 years in degenerative, calcific stenoses of tricuspid aortic valves. Patients with haemodynamically severe stenosis who had refused the recommended operation (n = 55) had an overall poor prognosis: mean survival averaged 23 +/- 5 months and the five-year probability of survival was 18 +/- 7%. All these patients died within 12 years of observation. Mean survival after the occurrence of angina pectoris was 45 +/- 13 months, after syncope 27 +/- 15 months, and after first occurrence of left heart failure 11 +/- 10 months.
398 citations
TL;DR: A multiple logistic regression analysis revealed that feelings of exhaustion were predictive of future myocardial infarction when controlling simultaneously for blood pressure, smoking, cholesterol, age and the use of antihypertensive drugs.
Abstract: To test the hypothesis that feelings of exhaustion are predictive of future coronary heart disease, a prospective study was done among 3877 males, aged 39-65. Feelings of exhaustion were assessed by the Maastricht Questionnaire. Among those who were free of coronary heart disease at screening, 59 subjects experienced a fatal or non-fatal myocardial infarction during the 4.2 year follow-up period. A multiple logistic regression analysis revealed that feelings of exhaustion were predictive of future myocardial infarction when controlling simultaneously for blood pressure, smoking, cholesterol, age and the use of antihypertensive drugs.
361 citations
TL;DR: After thrombolysis, residual infarct-related coronary stenoses in patients with their first acute myocardial infarction are not necessarily severely obstructive, which raises the problem of identifying which non-obstructive coronary stenosis are likely to occlude suddenly and why they do so.
Abstract: The sudden, often unheralded, onset of symptoms in acute myocardial infarction suggests that pre-existing coronary stenoses susceptible to acute thrombosis in the infarct-related artery may not necessarily have been severe. We investigated the severity of residual coronary stenoses after successful thrombolytic recanalization and the relationship to previous symptoms, collateral vessels and the extent of coronary artery disease in 60 consecutive patients at the time of presentation of their first acute myocardial infarction by performing quantitative coronary arteriography before, during and after intracoronary thrombolytic therapy. Recanalization was achieved in 48 (80%) patients with a residual stenosis of 58.1 +/- 10.8% (mean +/- ISD; range 33-82%) obstruction diameter and a minimum lumen calibre of 1.10 +/- 0.3 mm (range 0.39-1.95 mm). A residual stenosis of less than 60% obstruction diameter was present in 28 (47%) patients. When residual stenoses were mild, no acute collateral filling of the occluded artery was observed. After thrombolysis, residual infarct-related coronary stenoses in patients with their first acute myocardial infarction are not necessarily severely obstructive. This raises the problem of identifying which non-obstructive coronary stenoses are likely to occlude suddenly and why they do so.
287 citations
TL;DR: Patients with advanced interatrial block and retrograde activation of left atrium had a much higher incidence of paroxysmal supraventricular tachyarrhythmias and frequent atrial extrasystoles, while the control group, with aLeft atrium of the same size, but with less incidence of atrial Extentoles, had aMuch lower incidence ofParoxys mal tachycardia.
Abstract: We studied 16 patients with electrocardiographic evidence of advanced interatrial block and retrograde activation of the left atrium (P≥0.12 s, and diphasic (±) P waves in leads II, III, and VF). Eight patients had valvular heart disease, four had dilated cardiomyopathy and four had other forms of heart disease. Patients with valvular heart disease and cardiomyopathy were compared with a control group of 22 patients with similar clinical and echocardiographic characteristics, but without this type of interatrial block.
Patients with advanced interatrial block and retrograde activation of the left atrium had a much higher incidence of paroxysmal supraventricular tachyarrhythmias (93.7%) during follow-up than did the control group, (27.7%) (P>0.001). Eleven of 16 patients (68.7%) with advanced interatrial block and retrograde activation of left atrium had atrial flutter (atypical in seven cases, typical in two cases, and with two or more morphologies in two cases). Six patients from the control group (27.7%) had sustained atrial tachyarrhythmias (five atrial fibrillation and one typical atrial flutter). The atrial tachyarrhythmias were due more to advanced interatrial block and retrograde activation of left atrium and frequent atrial extrasystoles than to left atrial enlargement, because the control group with a left atrium of the same size, but without advanced interatrial block and retrograde activation of left atrium and with less incidence of atrial extrasystoles, had a much lower incidence of paroxysmal tachycardia.
253 citations
TL;DR: Diabetics with MI have a poor prognosis despite improvements in coronary care and the high late mortality is to a large extent related to a high proportion of fatal reinfarctions.
Abstract: The occurrence of diabetes mellitus and its complications and prognosis in an unselected consecutive series of patients with myocardial infarction (MI) was studied. Out of 341 patients 81 (24%) had diabetes. Comparisons were made between patients with and without diabetes. Age was higher and female sex more common among patients with diabetes. A considerable proportion of patients with diabetes were on digitalis when admitted (51%) compared to 20% of those without. Ventricular tachyarrhythmias requiring treatment did not differ between the two groups. High-degree AV-block was considerably more common among patients with diabetes (19%) than those without (7%; P less than 0.001). Mortality was higher in diabetic than in non-diabetic patients both during the hospital phase (25%, vs. 16%; P less than 0.02) and during one year of follow-up (53% vs. 28%; P less than 0.001). Diabetes was an independent prognostic risk factor for death (P less than 0.01). Fatal reinfarction was more common among diabetic patients (30%) than those without (14%; P less than 0.05). In conclusion diabetics with MI have a poor prognosis despite improvements in coronary care. The high late mortality is to a large extent related to a high proportion of fatal reinfarctions.
213 citations
TL;DR: The inverse direction of the association between leisure time physical activity and coronary risk factors suggests that increased physical activity alters the risk factor profile in a favourable direction.
Abstract: Physical activity at work and during leisure time were studied by using a questionnaire in a random sample of 7495 middle-aged men from the Primary Prevention Study in Goteborg and in 1273 able-bodied male patients with a first myocardial infarction, registered in the Infarction Register in the same city over the period 1968-84. Data on coronary risk factors and socio-economic factors were recorded in the population sample as were data on risk factors and known somatic predictors for prognosis in the infarction group. An inverse and graded association was found between leisure time physical activity and mean diastolic blood pressure, total cholesterol, body mass index, tobacco smoking, socio-economic status and mental stress in the random sample. During the approximate 12-year follow-up, low physical activity during leisure time, but not at work, was associated with an increased risk of coronary deaths and non-fatal infarctions in univariate analysis. Inactive subjects had twice the incidence of total coronary events (9.4%) as physically active contemporaries (4.2%). After controlling for major coronary risk factors, occupational class, diabetes, family history of coronary heart disease and mental stress in a multivariate logistic regression analysis, the association between leisure time physical activity and total coronary events disappeared. Physical activity at work and during leisure time estimated for the 12-month period preceding the first infarction was not associated with long-term prognosis after infarction. Infarction patients assessed to be in need of additional rehabilitation due to somatic restrictions, work-related factors and emotional instability, resumed work later and had a higher mortality and non-fatal recurrence rate during follow-up than patients not considered to require additional rehabilitation. Physical inactivity was not a risk factor for primary and secondary coronary events in this study. The inverse direction of the association between leisure time physical activity and coronary risk factors suggests that increased physical activity alters the risk factor profile in a favourable direction.
192 citations
TL;DR: It is concluded that in the failing human heart the number of cardiac beta-adrenoceptors is reduced proportional to the severity of heart failure and the catalytic subunit of the adenylate cyclase and the cAMP-dependent protein kinases may be promising targets for drugs to restore force of contraction in human heart failure.
Abstract: Cardiac beta-adrenoceptors and the positive inotropic effects of adenylate cyclase-depentdent (dobutamine, histamine, forskolin) and adenylate cyclase-independent agents (isobutylmethylxanthine (IBMX), dibutyryl-cAMP (db-cAMP), digoxin, digitoxin and calcium were measured in papillary muscle strips from severely failing (NYHA IV), moderately failing (NYHA II–III) and non-failing (NYHA I) human hearts. The density of beta-adrenoceptors in three NYHA I patients were 40.0, 42.0 and 42.9 fmol mg−1protein. The density of cardiac beta-adrenoceptors was significantly reduced in NYHA II–III to 18.0 ±1.1 mg−1 protein (n =16) and further reduced in NYHA IV to 9.5±1.6 fmol mg−1 protein (n=7). The KD values did not differ between the groups. Correspondingly, the positive inotropic effect of dobutamine was significantly reduced in NYHA II–II and almost lost in NYHA IV. The positive inotropic effect of histamine was similar in non-failing and moderately failing myocardium but reduced in preparations from severely failing hearts (NYHA IV). The positive inotropic effect of IBMX was diminished in moderately and severely failing myocardium depending on the functional class of heart failure. In contrast, the effects of forskolin, db-cAMP, digoxin and digitoxin were not impaired in NYHA IV when compared with the maximal positive inotropic effect of calcium. It is concluded that in the failing human heart (a) the number of cardiac beta-adrenoceptors is reduced proportional to the severity of heart failure; (b) the receptor coupling of H2-receptors to adenylate cyclase may be impaired, but only in severe heart failure; (c) the basal cAMP formation may be diminished; and that (d) the catalytic subunit of the adenylate cyclase and the cAMP-dependent protein kinases may be promising targets for drugs to restore force of contraction in human heart failure.
190 citations
TL;DR: Patients with recent onset atrial fibrillation can safely be converted to sinus rhythm using oral or intravenous regimens of flecainide.
Abstract: The efficacy and safety of oral (up to 400 mg in 3 h) and intravenous regimens (up to 150 mg in 10 min) of flecainide acetate were compared in the acute conversion of atrial fibrillation to sinus rhythm. Acute conversion was defined as conversion occurring within 5 h (oral) or within 30 min (intravenous regimen). Following classification in recent onset (duration less than 24 h) atrial fibrillation (n = 27) and chronic (greater than 24 h) atrial fibrillation (n = 13), patients were randomly assigned to one of the two regimens. In the group of patients with recent onset atrial fibrillation, 10 out of 14 (oral treatment) and 10 out of 13 (intravenous treatment) responded acutely. Approximately half of responding patients converted after the first oral dose or within the infusion time. In contrast, no patient with chronic atrial fibrillation showed conversion on flecainide. No serious adverse effects were encountered with the regimens used, not even in patients concomitantly using digitalis or verapamil. Thus, patients with recent onset atrial fibrillation can safely be converted to sinus rhythm using oral or intravenous regimens of flecainide.
169 citations
TL;DR: Patients with severe hypertrophic cardiomyopathy with dual chamber pacing improved and objectively there was an increase in exercise tolerance during paced rhythm.
Abstract: Patients with severe hypertrophic cardiomyopathy pase a difficult management problem. Between 1984 and 1986, 11 such patients have been treated by dual chamber pacing. (DDD). Subjectively all patients improved and objectively there was an increase in exercise tolerance during paced rhythm.
146 citations
TL;DR: From the results of this study, disopyramide seems to be a useful drug in maintaining sinus rhythm after electroconversion of atrial fibrillation.
Abstract: In this multicentre study, 90 patients who left hospital in sinus rhythm after electroconversion of atrial fibrillation were randomized to double-blind treatment with either disopyramide (n = 44) or placebo (n =46). The groups were comparable regarding age and sex distribution, duration of atrial fibrillation, heart volume and NYHA-classification. Life-table analysis was used to estimate the percentage of patients still in sinus rhythm and tolerating treatment at control visits after 1,3,6,9 and 12 months. After 1 month there was already a significant difference (P<0.01) between the two groups (disopyramide 70%, placebo 39%), a difference that was still remaining after 12 months (disopyramide 54%, placebo 30%). Twenty-four patients, all relapsing to atrial fibrillation before six months on placebo, were converted to sinus rhythm once again. They were then treated with disopyramide in an open manner and after 12 months 37% were still in sinus rhythm. From the results of this study, disopyramide seems to be a useful drug in maintaining sinus rhythm after electroconversion of atrial fibrillation.
TL;DR: Sixty-two Holter recordings of sudden death due to ventricular fibrillation (VF) were analysed by full disclosure and computerized processing and the prematurity index was lower in primary VF than in VT leading to VF, and the coupling interval of the extrasystole initiating VT/VF was shorter than the shortest value encountered before.
Abstract: Sixty-two Holter recordings of sudden death due to ventricular fibrillation (VF) were analysed by full disclosure and computerized processing. Thirteen sudden deaths were due to torsades de pointes in non coronary subjects (11/13), related to quinidine-like drugs and/or hypokalaemia: they were always initiated by a long RR cycle due to a post-extrasystolic pause, and announced by a progressive decrease of mean heart rate (from 77.5 ± 2.5 to 60.6 ± 2.7 beats min−1, P<0.001), in the three preceding hours. The other cases occurred in coronary patients (45/49), with acceleration of ventricular tachycardia ( VT), monomorphic in 24 cases, polymorphic in 13, the ventricular rate increasing from 220.6 ±55 to 241.5 ±69 beats min−1, rather than with primary VF (12 cases). A cardiac pause (RR cycle exceeding 125% of the mean five preceding cycles) was present in 22/49 cases immediately before the onset of VT/VF. The coupling interval of the extrasystole initiating VT/ VF was shorter than the shortest value encountered before: 377.6 ±± 94.5 ms vs 421.4 ± 92.3. The prematurity index (coupling interval/preceding RR cycle ratio) was lower in primary VF than in VT leading to VF. In the last hour preceding VF, ST changes were unusual (five cases), whereas heart rate increased from 82.8±20 to 92.0 ± 26.7 beats min−1, (P<0001).This acceleration was in fact present only in cases without pauses before the onset of VT/VF: from 85.0±22.8 to 99.1 + 31.1 (n = 27, P<0.001) whereas no change occurred in cases with preceding pause: from 79.8 ±15.5 to 80.8 ±16.3 (n = 22, P = NS). As a result, VT/VF without a preceding pause occurs in the setting of a higher heart rate, most probably reflecting a higher sympathetic drive. Prevention of these two main determinants by pacing and beta-blocking therapy should be more efficient than the use of antianginal or antiarrhythmic drugs.
TL;DR: It is concluded that programmed electrical stimulation induces the same type of ventricular arrhythmia (rapid polymorphic ventricular tachycardia or ventricular fibrillation) in 'symptomatic" and 'asymptomatic' patients with hypertrophic cardiomyopathy, the incidence in the latter group being 19%.
Abstract: Programmed electrical stimulation was performed in 54 consecutive patients with hypertrophic cardiomyopathy. There were 11 ‘symptomatic’ patients: three had a history of cardiac arrest due to ventricular tachyarrhythmias (group A), and eight had a history of syncope of unknown origin (group B); 43 patients were ‘asymptomatic’, i.e. they had no documented or suspected symptomatic ventricular arrhythmias (group C). There were no differences among the groups with respect to electrocardiographic, echocardiographic or hemodynamic data. Ventricular arrhythmias were induced by atrial and right and left ventricular stimulation with a maximum of two extrastimuli in 18 patients. Induced arrhythmias were repetitive ventricular response in six patients, nonsustained ventricular tachycardia in four, sustained ventricular tachycardia in five, and ventricular fibrillation in three patients. With one exception, ventricular tachycardia was always rapid (cycle lengths ranged from 180 to 250 ms); it was polymorphic in six patients and monomorphic in three. Atrial stimulation induced rapid monomorphic ventricular tachycardia in one group A patient. The type and incidence of induced ventricular arrhythmias did not differ among the three groups. It is concluded that programmed electrical stimulation induces the same type of ventricular arrhythmia (rapid polymorphic ventricular tachycardia or ventricular fibrillation) in ‘symptomatic’ and ‘asymptomatic’ patients with hypertrophic cardiomyopathy, the incidence in the latter group being 19%. Induction by atrial stimulation of a rapid ventricular tachycardia may be a specific finding to identify patients with hypertrophic cardiomyopathy at risk for exercise-induced ventricular fibrillation.
TL;DR: It is concluded that the use of atenolol (started 72 h before operation) is effective in reducing the incidence of supraventricular arrhythmias following elective coronary artery bypass operations in patients with good left ventricular function.
Abstract: Sixty patients undergoing coronary artery bypass surgery were studied prospectively in order to investigate the effect of a cardioselective beta-blocker on the incidence of postoperative supraventricular arrhythmias. Patients with good left ventricular function were randomly divided into two groups: 30 patients treated with atenolol and 30 patients acting as controls. Atrial fibrillation was seen in 11 patients and frequent premature atrial extrasystoles were noted in one. Eleven (37%) patients in the control group experienced arrhythmias whilst atenolol significantly reduced this incidence to 3% (one patient), P = 0.001. There was no significant relationship between the development of supraventricular arrhythmias and the following variables: age, sex, severity of preoperative symptoms, previous myocardial infarction, extent of coronary artery disease, technique of myocardial preservation used, ischaemic time, number and site of saphenous vein grafts, endarterectomies performed and perioperative serum potassium levels. It is concluded that the use of atenolol (started 72 h before operation) is effective in reducing the incidence of supraventricular arrhythmias following elective coronary artery bypass operations in patients with good left ventricular function.
TL;DR: Impairment in LV contractility as assessed from fractional shortening appears to be the most common echocardiographic finding, followed by LV wall thinning, pericardial effusion and eventually by LV cavity dilation, which supports the hypothesis that dilated cardiomyopathy may be a cardiac complication of AIDS.
Abstract: Few data are available about cardiac involvement in AIDS. We examined 102 consecutive patients with AIDS diagnosed clinically and serologically (Walter Reed Stage 5 and 6), by means of TM and cross-sectional echocardiography with the aim of detecting cardiac abnormalities. None of the patients had overt clinical signs of heart failure. Fifty-five (54%) patients showed persistent tachycardia, diminished left ventricular (LV) wall thickness (mean 7.6 +/- 0.2 mm) and decreased percentage LV fractional shortening (27 +/- 5). In 42 (41%) there was a globular and poorly contracting LV. Thirty-nine (38%) patients had pericardial effusion which was moderate in 30 and small in nine. In four patients, valvular endocarditic vegetation was shown--on the tricuspid valve in three, on the aortic valve in one: all of them were drug addicts; in three (2.9%) patients a cardiac mass was found which proved to be a localization of Kaposi's sarcoma in two. Twenty-five (24.5%) patients died; necropsy showed cardiac chamber dilation, and thin LV walls in 18. On microscopic examination, myocardial fibrosis and lymphocyte infiltration with cell necrosis were observed. We conclude that cardiac abnormalities are common in AIDS. Impairment in LV contractility as assessed from fractional shortening appears to be the most common echocardiographic finding, followed by LV wall thinning, pericardial effusion and eventually by LV cavity dilation. This evolution is suggestive of myocardial damage and supports the hypothesis that dilated cardiomyopathy may be a cardiac complication of AIDS.
TL;DR: Right ventricular infarction may be secondary to pulmonary hypertension in the setting of massive pulmonary embolism, even in the absence of right ventricular hypertrophy and with normal or stenotic coronary arteries.
Abstract: Isolated right ventricular infarction has been found in cases of right ventricular hypertrophy, but there are no reports on right ventricular infarction secondary to massive pulmonary embolism. Six autopsied patients with massive pulmonary embolism and pure right ventricular infarction, suspected to be secondary to the embolism, were selected from a population of 216 autopsies. Pulmonary embolism was the suspected diagnosis in five cases due to typical clinical, electrocardiographic and haemodynamic data. Right ventricular infarction was a post-mortem finding, not previously diagnosed. In every case the thickness of the right ventricular myocardium was normal. The necrosis of the right ventricle was transmural in four cases and subendocardial in two and the entire right ventricular wall (anterolateral as well as posterior) was involved. No mural thrombi were present and in no case did the necrosis involve the left ventricle. In one case the coronary arteries were normal, in the other five significant lesions of the right or left coronary arteries were observed. These lesions may have been, in part, responsible for the necrosis of the right ventricle when the massive pulmonary embolism was added. We conclude that right ventricular infarction may be secondary to pulmonary hypertension in the setting of massive pulmonary embolism, even in the absence of right ventricular hypertrophy and with normal or stenotic coronary arteries.
TL;DR: Assessment of myocardial structure from LV endomyocardial biopsies revealed no differences in muscle fibre diameter, interstitial fibrosis and volume fraction of myofibrils between patients with aortic stenosis having a normal and those with a depressed ejection fraction.
Abstract: In aortic valve stenosis, concentric hypertrophy develops which is characterized by a reduced end-diastolic radius-to-wall thickness ratio (r/h) with an essentially normal cavity shape. As long as the product of (r/h) and LV systolic pressure remains constant, hypertrophy is appropriate. An increase in the product, which represents an increase in wall stress signals inadequate LV hypertrophy. Although at first glance, massive LV hypertrophy appears favourable for the maintenance of a normal LV ejection fraction in aortic stenosis, data from 23 studies of the literature have shown an inverse relationship between ejection fraction and LV angiographic mass m-2 (r = -0.59). Both a degree of hypertrophy inadequate to keep systolic wall stress within normal limits and a reduction of LV contractility may explain the depression of ejection fraction when LV angiographic mass is sizeably increased. Conversely, a normal ejection fraction in aortic stenosis may not be indicative of normal systolic myocardial function under all circumstances. In the presence of mildly reduced contractility, a normal ejection fraction may be maintained by the use of preload reserve. Assessment of myocardial structure from LV endomyocardial biopsies revealed no differences in muscle fibre diameter, interstitial fibrosis and volume fraction of myofibrils between patients with aortic stenosis having a normal and those with a depressed ejection fraction. Preoperative ejection fraction is a poor predictor of postoperative survival, whereas markedly increased preoperative angiographic mass and end-systolic volume have been reported to predict an unsatisfactory postoperative outcome characterized by either death or poor LV function.
TL;DR: The study showed that the EA ratio measured proximal to the mitral valve was significantly smaller than theEA ratio measured distal (in the left ventricle) and that the only prominent relations with the EA ratios were those with age and heart rate.
Abstract: Pulsed Doppler measurements on both sides of the mitral valve and M-mode left ventricular echocardiograms were performed in 215 healthy subjects, 120 males and 95 females, between one and 65 years old, in order to evaluate normal diastolic filling patterns of the left ventricle. The relation between the maximum blood velocity during early passive filling (Ewave) and during atrial contraction (A wave) was computed from the Doppler spectra obtained proximal and distal to the mitral valve, resulting in the EA ratio. The influence on the EA ratio of age, gender, body surface area, blood pressure, heart rate, PR interval, respiration, wall thickness and basal wall mass of the left ventricle was investigated.
The study showed that the EA ratio measured proximal to the mitral valve (in the left atrium) was significantly smaller than the EA ratio measured distal (in the left ventricle) and that the only prominent relations with the EA ratio were those with age and heart rate. The EA ratio declines with age: proximal to the mitral valve from approximately (medians) 2.5 to 1 and distal to it from 3.5 to 1.5. All other physiological variables are weakly related or unrelated to the EA ratio in this group of healthy subjects.
TL;DR: The findings indicate that certain electrical or morphological conditions are required for the occurrence of arrhythmias and changes which are specific to ARVD are identified.
Abstract: Temporal signal averaging of the surface QRS (VI + V3 + V5) was performed in 16 patients with arrhythmogenic right ventricular dysplasia and in 16 normal subjects. The differences between ARVD patients and normals were large for the filtered QRS duration (FQRSd) (146.2±18.9 vs. 91.8±4.1ms, P<000001), the late potential duration (LPd) (83.5±23.3 ms vs. 23.6±4.6ms, P< 0.00001), the LPd/ FQRSd ratio (53.9± 10.1% vs. 25.8±5.1%, P <0.00001), the filtered QRS amplitude (234.0±61.1μV vs. 429±942 fiV, P <0001), and the root mean square voltage of the signals in the terminal 40 and 50 ms of the FQRS (RMS40 and RMS50) (18.4± 10.0μV vs. 118.4±49.8p.V, P<0.0005 and 27.9± 19.2μV vs. 217.0±66.3fiV, P<0000002). RMS50 <40μV discriminated best between ARVD and normals (81% sensitivity and 100% specificity). The right-sided predominance of the abnormalities in ARVD was demonstrated by the significantly longer FQRSd and LPd, and the higher ratio LPd/FQRSd in right than in left precordial leads. The arrhythmia susceptibility did not seem to influence the presence of or properties ofLP in the ARVD group. Patients with multiple QRS morphologies during ventricular tachycardia (VT) had, compared with patients with only one type of VT, longer LPd (108.3 ±46.4 ms vs. 64.2 ±31.7 ms, P<0.02) and lower RMS40 voltage (9.4±9.9 μV vs. 25.4±21.6 μV, P<0.05). The relative heart volume was positively correlated with delayed activity, but an enlarged heart was not apre-requisitefor the presence ofLP. The method thus identifies changes which are specific to ARVD. The findings indicate that certain electrical or morphological conditions are required for the occurrence of arrhythmias.
TL;DR: The results suggest that the thiol consuming transformation of organic nitrates into nitrite ions may lead to a depletion of cysteine stores, resulting in a decreased formation of NO and, consequently, in a decrease of guanylate cyclase activation, clinically arising as nitrate tolerance.
Abstract: We continuously studied the quantitative formation of nitric oxide (NO), nitrite and nitrate ions from several organic nitrate esters in the presence of various thiol-containing compounds by spectroscopy and HPLC. The results indicate that there are different pathways of decomposition depending on the chemical nature of the mercaptan tested. The amino acid cysteine is known to function as an essential cofactor for guanylate cyclase activation by organic nitrates in vitro. For comparison we investigated several structural analogues with respect to their nitric oxide or nitrite ion releasing potency. Both were found to represent the main products resulting from nitrate ester breakdown besides the respective alcohols. We found that only those compounds were able to activate the enzyme in the presence of nitroglycerin (GTN) which induce the release of NO as well. On the other hand, nearly all other thiols tested caused an in vitro decomposition of organic nitrates by producing excess nitrite and the corresponding disulfide without the formation of NO. Thus, the decomposition of organic nitrates to nitrite ions does not contribute at all to activation of guanylate cyclase. Our results confirm that the liberation of nitric oxide is the common principle of action for all nitrovasodilators. In addition, our results suggest that the thiol consuming transformation of organic nitrates into nitrite ions (ratio NO/nitrite 1:10) may lead to a depletion of cysteine stores, resulting in a decreased formation of NO and, consequently, in a decrease of guanylate cyclase activation, clinically arising as nitrate tolerance.
TL;DR: Reduction of the rapid ventricular rates seen in digitalized patients with AF does not appear to be of benefit in terms of improving either exercise tolerance or cardiac output.
Abstract: Six patients with chronic atrial fibrillation (AF) took single doses of digoxin, verapamil and diltiazem, alone and in combination. Three hours after dosing, resting and post-exercise heart rate, exercise tolerance and resting and post-exercise cardiac output were measured. Post-exercise heart rates ranged from 167 bpm (after placebo) to 122 bpm (after digoxin plus diltiazem) (P<0.05). However, the lower ventricular rates seen after treatment with the calcium antagonists were not assciated with improved exercise tolerance, which did not differ significantly between the various treatments. Reduction of the ventricular rate was associated with a small increase in stroke volume but the benefits of this were offset by a rate related reduction in cardiac output. Further reduction of the rapid ventricular rates seen in digitalized patients with AF does not appear to be of benefit in terms of improving either exercise tolerance or cardiac output.
TL;DR: Patients with and without angina pectoris and/or Raynaud's phenomenon did not differ in respect of age, histology of tumor or medication, but arterial occlusive event is a frequent and common toxicity and a result of treatment with PVB.
Abstract: Twenty-one consecutive patients with testicular cancer treated with bleomycin, vinblastine, and cisplatin (PVB) were evaluated for acute vascular ischaemic events during chemotherapy. Angina pectoris occurred in 8/21 (38%) patients, a median 5·6 weeks after initiation of chemotherapy and persisted for 2·7 days. Raynaud's phenomenon was detected in seven (33%) subjects, transient ischaemia of the toes was found in six (29%) patients, one patient complained of migraine, but none had major cerebrovoscular accidents. Patientswith and without angina pectoris and/or Raynaud's phenomenon did not differ in respect of age, histology of tumor or medication. Ischaemia occurred at any time during the course of chemotherapy. No correlation was found between dosage of drugs and time of onset of ischaemic reactions. However, arterial occlusive event is a frequent and common toxicity and a result of treatment with PVB.
TL;DR: Intravenous thrombolytic therapy has become a routine therapeutic intervention in acute myocardial infarction and its success in the general hospital community noninvasive methods are needed to evaluate its success, and the effect of infarct reperfusion on the times to peak value of myoglobin, CKMB, and CK were studied.
Abstract: Intravenous thrombolytic therapy has become a routine therapeutic intervention in acute myocardial infarction. In order to evaluate its success in the general hospital community noninvasive methods are needed. Therefore, the effect of infarct reperfusion on the times to peak value of myoglobin. CKMB, and CK were studied in patients with acute myocardial infarction. Recanalization of the occluded coronary artery was achieved by intracoronary infusion of streptokinase in eight patients within 3·5 h, and in 18 patients more than 3·5 h after onset of pain. In 10 patients, the coronary artery remained occluded, and in eight patients thrombolysis was not attempted.
Analyzing the times to peak value of myoglobin, CKMB, and CK, the probability of correct classification of infarct reperfusion varied between 1 and 0·9, if recanalization was achieved within 3·5 h after onset of pain. The predictive power could be improved further by a combined analysis of the times to peak value of both myoglobin and CK. In cases where reperfusion was achieved more than 3·5 h after the onset of pain, the probability of correct classification of infarct reperfusion varied between 0·99 and 0·05. Among the marker proteins analyzed, myoglobin allowed the earliest and best discrimination between reperfusion or no reperfusion.
Thus, by applying the time to peak value analysis, infarct reperfusion can only be predicted reliably if it is achieved early after onset of pain.
TL;DR: Cross-sectional echocardiography provides highly reproducible measurements of right ventricular size and contraction patterns even in patients with wall shape deformities, and is therefore a feasible non-invasive method for the evaluation of right-sided myocardial abnormalities in Patients with ARVD.
Abstract: Twenty patients with arrhythmogenic right ventricular dysplasia (ARVD) and 20 healthy volunteers underwent cross-sectional echocardiographic examination for the assessment of ventricular dimensions and wall motion. Right ventricular cavity diameters and wall segments were selected from the inflow and outflow tracts and the right ventricular body. The measurement error for measuring cavity dimensions was low throughout and the reproducibility of wall motion scoring was high in both the normal subjects and the patients. All except one patient had increased dimensions and/or abnormal wall motion in the right ventricle. The right ventricular inflow tract was dilated in nine patients, the outflow tract in 11 patients and the short- or long-axis diameters of the right ventricular body were increased in seven patients. Right ventricular wall motion abnormalities, being the most frequent finding, ranged from mild hypokinesia only to dyskinesia or sacculations, and were fairly evenly distributed among the segments studied. Left ventricular abnormalities, found in eight patients, were generally mild. Cross-sectional echocardiography thus provides highly reproducible measurements of right ventricular size and contraction patterns even in patients with wall shape deformities, and is therefore a feasible non-invasive method for the evaluation of right-sided myocardial abnormalities in patients with ARVD. The diagnostic accuracy of this technique warrants further clarification.
TL;DR: Measures of breathlessness and lung function could be more widely used in clinical situations and in screening as additional independent indicators of both unrecognized IHD and of risk for major IHD events.
Abstract: Men with moderate of severe breathlessness had a greater than two-fold risk of suffering a major ischaemic heart disease (IHD)event compared to men with no evidence of breathlessness,based on 7.5-year follow-up in a prospective study of 7735 British men aged 40–59 years. Even after adjustment for other risk factors, including cigarette smoking, the relative risk remained two-fold. Men in the lowest fifth of the forced expiratory volume is 1 s (FEV1)distribution also had a two-fold risk of IHD compared to men in the highest fifth after similar adjustment. In part, the role of breathlessness as a risk factor for major IHD events was explained by its strong association with pre-existing, but usually undiagnosed, IHD. However,breathlessness was associated with an increased risk of heart attack even in men without any evidence of pre-existing IHD at screening. FEV1 was related to risk of a major IHD event in men without evidence of pre-existing IHD at screening and in men withn previously undiagnosed IHD detected at screening. Measures of breathlessness and lung function could be more widely used in clinical situations and in screening as additional independent indicators of both unrecognized IHD and of risk for major IHD events.
TL;DR: Doppler indexes that represent a measure of isovolumic relaxation and the early filling phases of diastole showed small variability; however, serial changes in the atrial contribution to ventricular filling identified by these indexes should probably be interpreted with some caution.
Abstract: The present investigation was undertaken in 12 normal subjects to determine the magnitude of technical and biologic variability of six previously validated Doppler indexes of diastolic function Variability due to the reader was small for each of the six Doppler indexes Variability due to the technician was larger than for the reader, and day-to-day variability was larger than variability due to either the reader or techinician for the great majority of the comparisions (ie, 21 of 24) Four Doppler indexes assessing early diastolic events (isovolumic relaxation, duration of the early diastolic peak of flow-velocity, rate of decrease of flow-velocity in early diastole, and maximal early diastolic flow-velocity) did not show statistically significant changes due to day-to-day variability The two Doppler indexes assessing late diastolic events [maximal late diastolic (atrial) flow-velocity, and the ratio between maximal early and late flow-velocity] showed greater change on a day-to-day basis (P<005)
In conclusion, Doppler indexes that represent a measure of isovolumic relaxation and the early filling phases of diastole showed small variability Indexes that measure the late filling phase of diastole, such as maximal late (atrial) diastolic flow-velocity and the ratio between early and late diastolic flow-velocities, showed relatively large day-to-day variability; therefore, serial changes in the atrial contribution to ventircular filling identified by these indexes should probably be interpreted with some caution
TL;DR: The thesis that acquired QT interval (or QTc) prolongation reflects physiological disturbance similar to those found in the congential syndromes has been assumed to be of central importance in many studies of QT prolongation in the clinical setting but there is no evidence to support this assumption.
Abstract: The thesis (stated or implied) that acquired QT interval (or QTc) prolongation reflects physiological disturbance similar to those found in the congential syndromes has been assumed to be of central importance in many studies of QT prolongation in the clinical setting. There is no evidence to support this assumption. It is suggested that the use of rate correction of the measured QT interval has obscured our understanding of repolarization abnormalities. Although a QT interval corrected for heart rate may reflect a relationship between the duration of repolarization and heart rate in a single value (e.g. QTc) the corrected value clearly embodies complex influences other than those directly due to rate and for which no 'correction' is, as yet, possible.
TL;DR: Objective evidence of ongoing ischaemia despite medical treatment has a guarded short-term prognosis, and 'Stabilization' of unstable angina may be incomplete as long as transient ischaemic at rest can still be detected.
Abstract: The occurrence of unstable angina pectoris, despite medical treatment, is generally regarded as an ominous prognostic sign and an indication for invasive diagnosis and revascularization. We investigated 38 consecutive patients with severe unstable angina with a mean of 2.5 days of continuous two-channel, frequency modulated Holter monitoring for ST segment analysis. In 16 patients, transient ischaemic episodes (more than 0.1 mV lasting more than 1 min) occurred despite maximal medical treatment: 82% of the episodes were silent. Compared to the 22 patients without ischaemic episodes there were no significant differences in prevalence of risk factors, numbers of vessels diseased (69% vs. 74% triple-vessel disease) or ejection fraction (54±15% vs. 53±16%). The 30-day prognosis, however, varied: of 16 patients with ischaemic episodes, 14 (88%) had a subsequent cardiac event (death, AMI, PTCA or CABG) compared to only 10 of 22 patients (45%) without ischaemic episodes (P < 0.02 for all events, P <0.1 for death/ AMI only).
Transient ischaemic episodes, predominantly silent, are frequent in patients with severe unstable angina. Objective evidence of ongoing ischaemia despite medical treatment has a guarded short-term prognosis. ‘Stabilization’ of unstable angina may be incomplete as long as transient ischaemia at rest can still be detected.
TL;DR: There is no sound evidence that procedural factors or drug regimens are capable of reducing the recurrence rate of restenosis, and efforts to find ways of reducing restenoses after coronary angioplasty are commendable and necessary.
Abstract: The average restenosis rate reported so far in the literature is just below 30%. Although restenosis correlates well with the recurrence of symptoms, the two factors are not identical. The incidence of myocardial infarction during the first 2 years after coronary angioplasty is 4% and the incidence of death is 2%. These two cardiac events are rarely the first symptom of restenosis. Restenosis, therefore, is not primarily a life threatening disease but still deserves prompt evaluation and correction. Restenosis is stenosis-related rather than patient-related. Thus, restenosis rate per patient increases with the number of lesions or arteries treated. Restenosis rates vary considerably with centres. Serial analyses of restenosis rates at individual centres revealed that the restenosis rates remained constant at a centre-specific level. Differences in case selection and particularities in data definition and analysis may account for both these observations. There is no sound evidence that procedural factors (balloon size, number, duration, or pressure of inflations, etc.) or drug regimens are capable of reducing the recurrence rate. All risk factors for restenosis identified so far are difficult to influence. Extinguishable factors such as smoking seem of little importance in this particular problem. Efforts to find ways of reducing restenoses after coronary angioplasty are commendable and necessary. Their chance of success, however, is small. 'Old customers' will continue to represent 20-30% of the clientele for coronary angioplasty. Their risk for failure and complications is small, but they do carry a considerable risk of restenosis.
TL;DR: The most likely explanation for the prolonged survival on the effective vasodilator regimen is that these drugs tend to increase left ventricular ejection fraction, probably by a sustained effect on preload and impedance.
Abstract: The reduction of mortality in patients with chronic congestive heart failure treated with the vasodilator regimen hydralazine and isosorbide dinitrate compared to those treated with placebo or prazosin in the Veterans Administration Cooperative Study (V-HeFT) was examined in order to explore the possible mechanism of the favourable effect. Similar efficacy in coronary and non-coronary disease patients tends to discount a prominent effect on myocardial perfusion. The most likely explanation for the prolonged survival on the effective vasodilator regimen is that these drugs tend to increase left ventricular ejection fraction, probably by a sustained effect on preload and impedance.