Showing papers by "Ernst E. van der Wall published in 2004"

Relationship between QRS duration and left ventricular dyssynchrony in patients with end-stage heart failure.

Abstract: Introduction: Patients with end-stage heart failure and a wide QRS complex are considered candidates for cardiac resynchronization therapy (CRT). However, 20% to 30% of patients do not respond to CRT. Lack of left ventricular dyssynchrony may explain the nonresponse. Accordingly, we evaluated the presence of left ventricular dyssynchrony using tissue Doppler imaging (TDI) in 90 consecutive patients with heart failure. Methods and Results: Ninety patients with severe heart failure (left ventricular ejection fraction 150 ms). All patients underwent TDI to assess left ventricular dyssynchrony. Extensive left ventricular dyssynchrony was defined as an electromechanical delay on TDI between the septum and lateral wall, the so-called septal-to-lateral delay, of >60 ms. Severe dyssynchrony was observed in 27% of patients with narrow QRS complex, 60% with intermediate QRS duration, and 70% with wide QRS complex. No relation existed between QRS duration and septal-to-lateral delay. Conclusion: From 30% to 40% of heart failure patients with QRS duration >120 ms do not exhibit left ventricular dyssynchrony, which may explain the nonresponse to CRT. Alternatively, 27% of patients with heart failure and a narrow QRS complex show significant left ventricular dyssynchrony and may be candidates for CRT. (J Cardiovasc Electrophysiol, Vol. 15, pp. 544-549, May 2004)

Comparison of response to cardiac resynchronization therapy in patients with sinus rhythm versus chronic atrial fibrillation

Abstract: Cardiac resynchronization therapy (CRT) is a new therapeutic option for patients who have drug-refractory end-stage heart failure. Much information has been obtained from patients who have sinus rhythm, but the use of CRT in patients who have chronic atrial fibrillation (AF) has not been studied extensively. Accordingly, we evaluated the clinical response and long-term survival rate of CRT in patients who had heart failure and chronic AF, and the results were compared with those in patients who had sinus rhythm and who underwent CRT. Sixty patients who had end-stage heart failure (30 had sinus rhythm and 30 had chronic AF), New York Heart Association classes III to IV, left ventricular ejection fraction 120 ms, and a left bundle branch block received a biventricular pacemaker. New York Heart Association class, Minnesota Quality of Life score, and 6-minute walking distance were evaluated at baseline and after 6 months of CRT. Long-term follow-up was ≤2 years. New York Heart Association class, Minnesota Quality of Life score, and 6-minute walking distance improved significantly in the 2 groups after 6 months of CRT. The number of nonresponders was greater among patients who had AF. Nevertheless, the long-term survival rate was comparable between patients who had sinus rhythm and those who had AF. Patients who had AF demonstrated comparable benefit from CRT as those who had sinus rhythm.

QRS duration and shortening to predict clinical response to cardiac resynchronization therapy in patients with end-stage heart failure.

Abstract: Despite current selection criteria (NYHA Class III-IV, LVEF 120 ms with LBBB), 30% of patients do not benefit from cardiac resynchronization therapy (CRT). The use of QRS duration as selection criteria for CRT has not been evaluated systematically yet. Accordingly, the value of QRS duration at baseline (and reduction in QRS duration after CRT) to predict responders was studied. Patients were evaluated at baseline and after 6 months of CRT for NYHA Class, quality of life score, and 6-minute walk test. QRS duration was evaluated before, directly after implantation, and after 6 months of CRT. Sixty-one patients were included; 45 (74%) patients were classified as responders (improvement of NYHA Class, 6-minute walking distance and quality of life score) and 16 (26%) as nonresponders. QRS duration at baseline was similar between the two groups: 179 +/- 30 ms versus 171 +/- 32 ms, NS. Directly after implantation, QRS duration was reduced from 179 +/- 30 ms to 150 +/- 26 ms (P 10 ms had a high sensitivity (73%) with low specificity (44%); conversely, a > 50 ms reduction in QRS duration was highly specific (88%) but not sensitive (18%) to predict response to CRT. No optimal cutoff value could be defined. QRS duration at baseline is not predictive for response to CRT; responders exhibit a significant reduction in QRS duration after CRT, but individual response varies highly, not allowing adequate selection of responders.

Comparison of benefits from cardiac resynchronization therapy in patients with ischemic cardiomyopathy versus idiopathic dilated cardiomyopathy

Abstract: Cardiac resynchronization therapy (CRT) is a recently introduced therapeutic option for patients with severe heart failure and intraventricular conduction disturbances. However, it is estimated that 20% to 30% of patients may not respond to CRT. Patients with ischemic cardiomyopathy (IC) may respond less favorably to CRT compared with patients with idiopathic dilated cardiomyopathy (IDC). Accordingly, the beneficial effects of CRT were evaluated in 2 subsets of patients (IC and IDC). Seventy-four patients with end-stage heart failure, New York Heart Association (NYHA) class III or IV, left ventricular (LV) ejection fraction 120ms, and left bundle branch block received a biventricular pacemaker. At baseline and 6 months after implantation these parameters were evaluated: NYHA class, Minnesota quality-of-life score, QRS duration, and 6-minute walking distance. LV ejection fraction and severity of mitral regurgitation were assessed before and 6 months after CRT using 2-dimensional echocardiography. Long-term follow-up and hospitalization rates were obtained up to 2 years. Of the 74 patients, 46% (n = 34) had IC and 54% (n = 40) IDC. At 6 months follow-up all clinical parameters, QRS duration, LV ejection fraction, and mitral regurgitation improved significantly in both groups. Long-term (2-year) follow-up showed a survival rate of 87.5% for patients with IDC and 88.3% for patients with IC. The percentages of responders to CRT (defined as an improvement in NYHA class ≥1 grade) were comparable in both groups (65% vs 71%). Therefore, the underlying etiology of heart failure (IC vs IDC) was not related to the response to CRT.

Quantification of myocardial infarct size and transmurality by contrast-enhanced magnetic resonance imaging in men.

Abstract: Contrast-enhanced magnetic resonance (ce-MR) imaging allows precise delineation of infarct transmurality. An issue of debate is whether data analysis should be performed visually or quantitatively. Accordingly, a head-to-head comparison was performed between visual and quantitative analyses of infarct transmurality on ce-MR imaging. In addition, infarct transmurality was related to the severity of wall motion abnormalities at rest. In 27 patients with long-term ischemic left ventricular (LV) dysfunction (LV ejection fraction 33 ± 8%) and previous infarction, cine MR imaging (to assess regional wall motion) and ce-MR imaging were performed. Using a 17-segment model, each segment was assigned a wall motion score (from normokinesia to dyskinesia), and segmental infarct transmurality was visually assessed on a 5-point scale (0 = no infarction, 1 = transmurality ≤25% of LV wall thickness, 2 = transmurality 26% to 50%, 3 = transmurality 51% to 75%, and 4 = transmurality 76% to 100%). Quantification of transmurality was performed with threshold analysis; myocardium showing signal intensity above the threshold was considered scar tissue, and percent transmurality was calculated automatically. Wall motion was abnormal in 56% of the 459 segments, and 55% of segments showed hyperenhancement (indicating scar tissue). The agreement between visual and quantitative analyses was excellent: 90% of segments (κ 0.86) were categorized similarly by visual and quantitative analyses. Infarct transmurality paralleled the severity of contractile dysfunction; 96% of normal or mildly hypokinetic segments had infarct transmurality ≤25%, whereas 93% of akinetic and dyskinetic segments had transmurality >50% on visual analysis. In conclusion, visual analysis of ce-MR imaging studies may be sufficient for assessment of transmurality of infarction.

Head-to-Head comparison between Contrast-Enhanced magnetic resonance imaging and dobutamine magnetic resonance imaging in men with ischemic cardiomyopathy ☆

Abstract: Contrast-enhanced magnetic resonance imaging (MRI) can predict functional recovery after revascularization. Segments with small, subendocardial scars have a large likelihood of recovery, and segments with transmural infarction have a small likelihood of recovery. Segments with an intermediate extent of infarction have an intermediate likelihood of recovery, and therefore, additional information is needed. Accordingly, the transmurality of infarction on contrast-enhanced MRI was compared with low-dose dobutamine MRI to further define viability in 48 patients. Regional contractile dysfunction was determined by cine MRI at rest (17-segment model), and contractile reserve was determined using low-dose dobutamine infusion. Contrast-enhanced MRI was performed to assess the extent of scar tissue. A total of 338 segments (41%) were dysfunctional, with 61% having contractile reserve. Most segments (approximately 75%) with small, subendocardial scars (hyperenhancement scores 1 or 2) had contractile reserve, whereas contractile reserve was not frequently (17%) observed in segments with transmural infarction (hyperenhancement score 4) (p <0.05). Of segments with an intermediate infarct transmurality (hyperenhancement score 3), contractile reserve was observed in 42%, whereas 58% did not have contractile reserve. In conclusion, the agreement between contrast-enhanced MRI and low-dose dobutamine MRI is large in the extremes (subendocardial scars and transmural scars), and contrast-enhanced MRI may be sufficient to assess the likelihood of the recovery of function after revascularization. However, 61% of segments with an intermediate extent of scar tissue on MRI have contractile reserve and 39% lack contractile reserve. In these segments, low-dose dobutamine MRI may be needed to optimally differentiate myocardium with large and small likelihoods of functional recovery after revascularization.

Noninvasive Angiography and Assessment of Left Ventricular Function Using Multislice Computed Tomography in Patients With Type 2 Diabetes

Abstract: OBJECTIVE —Early identification of coronary artery disease (CAD) in patients with diabetes is important because these patients are at increased risk for CAD and have worse outcome than nondiabetic patients after CAD is diagnosed. Recently, noninvasive coronary angiography and assessment of left ventricular function has been demonstrated with multislice computed tomography (MSCT). The purpose of the present study was to validate this approach in patients with type 2 diabetes. RESEARCH DESIGN AND METHODS —MSCT was performed in 30 patients with confirmed type 2 diabetes. From the MSCT images, coronary artery stenoses (≥50% luminal narrowing) and left ventricular function (left ventricular ejection fraction, regional wall motion) were evaluated and compared with results of conventional angiography and two-dimensional echocardiography. RESULTS —Two hundred twenty of 256 coronary artery segments (86%) were interpretable with MSCT. In these segments, sensitivity and specificity for detection of coronary artery stenoses were 95%. Including the uninterpretable segments, sensitivity and specificity were 81 and 82%, respectively. Bland-Altman analysis in the comparison of left ventricular ejection fractions demonstrated a mean difference of −0.48 ± 3.8% for MSCT and echocardiography, which was not significantly different from 0. Agreement between the two modalities for assessment of regional contractile function was excellent (91%, κ statistic 0.81). CONCLUSIONS —Accurate noninvasive evaluation of both the coronary arteries and left ventricular function with MSCT is feasible in patients with type 2 diabetes. This noninvasive approach may allow optimal identification of high-risk patients.

Effect of left ventricular remodeling after cardiac resynchronization therapy on frequency of ventricular arrhythmias

Abstract: We evaluated whether cardiac resynchronization therapy affects the prevalence of ventricular tachycardia in relation to reverse remodeling in patients with end-stage heart failure. Clinical, echocardiographic, and implantable cardioverter-defibrillator (ICD) data of 17 patients with ICDs were obtained before and after they had received an upgrade to an ICD-cardiac resynchronization therapy device.

An integrated evaluation of endothelial constitutive nitric oxide synthase polymorphisms and coronary artery disease in men

Abstract: In the present study, we sought to evaluate the role of three polymorphisms in the ecNOS (endothelial constitutive nitric oxide synthase) gene in relation to the existence, severity and progression of CAD (coronary artery disease), MI (myocardial infarction) and the occurrence of ischaemia in a predominantly Caucasian population. Patients with CAD (n = 760) and age- and sex-matched population-based controls (n = 691) were genotyped for the -786T/C, E/D298 and 4a/b polymorphisms. Patients were randomized to pravastatin (40 mg) or placebo. Progression of atherosclerosis was evaluated by sequential angiography. Functionality was assessed by ST segment analysis of ambulant ECGs. The E298 (P = 0.003) and 4a (P = 0.001) alleles were associated with CAD. Furthermore, E298 (P = 0.009) and -786T (P = 0.022) alleles were associated with previous MI among patients, predominantly smokers. D/D298 homozygotes, but not -786T/C or 4a/4b mutants, had longer-lasting ischaemia than others (P < 0.05). We found no differences in progression of atherosclerosis, irrespective of pravastatin use. We conclude that the E/D298 polymorphism is most consistently associated with CAD, but not with progression of atherosclerosis. The E allele is associated with CAD and MI, whereas the D allele is associated with ischaemia. Chemicals / CAS: endothelial nitric oxide synthase, 503473-02-7; pravastatin, 81131-74-0; Anticholesteremic Agents; Nitric Oxide Synthase Type III, EC 1.14.13.39; Nitric Oxide Synthase, EC 1.14.13.39; NOS3 protein, human, EC 1.14.13.39; Pravastatin, 81093-37-0

Regional and global right ventricular dysfunction in asymptomatic or minimally symptomatic patients with congenitally corrected transposition.

Abstract: Patients with congenitally corrected transposition are at risk of right ventricular dysfunction and failure. With this in mind, we examined 13 patients with congenitally corrected transposition, 7 not having undergone surgery, and 6 after physiological repair, comparing them with 6 healthy subjects matched for age and sex, using cardiac magnetic resonance imaging, at rest and during dobutamine stress, in order to determine regional and global right ventricular response to stress. At rest, the patients had significantly decreased overall wall motion compared to their healthy peers (7.2 +/- 0.5, versus 9.8 +/- 0.4 mm). During infusion of dobutamine, overall wall motion increased to 12.8 +/- 0.4 mm in the healthy subjects, versus 8.8 +/- 1.0 mm in patients. At the regional level, significant differences in mural motion were found between patients and controls in the anterior (9.5 +/- 1.1, versus 13.2 +/- 0.6 mm), posterior (10.2 +/- 1.6, versus 13.2 +/- 0.8 mm), and septal segments (5.0 +/- 0.8, versus 11.2 +/- 0.6 mm). At rest, overall mural thickening in patients was similar to that of controls, but significantly less in patients during stress. During dobutamine stress, patients showed significantly less regional wall thickening than controls, particularly in the septal (2.7 +/- 0.6, versus 6.0 +/- 0.4 mm, respectively) and in the anterior segments (4.2 +/- 0.6, versus 7.8 +/- 0.6 mm, respectively). Right ventricular ejection fraction strongly correlated with mural motion and thickening, both at rest and during stress. Abnormal regional function in the systemic morphologically right ventricle may occur in patients with congenitally corrected transposition, which strongly correlates with right ventricular ejection fraction. Our findings support the hypothesis that, in patients with congenitally corrected transposition, ischemia of the right ventricular myocardium contributes to the development of right ventricular dysfunction.

Anatomical observations of the pulmonary veins with intracardiac echocardiography and hemodynamic consequences of narrowing of pulmonary vein ostial diameters after radiofrequency catheter ablation of atrial fibrillation

Abstract: Intracardiac echocardiography was used to explore pulmonary venous (PV) anatomy and to monitor PV stenosis in 31 patients referred for radiofrequency catheter ablation at PV ostia. Interindividual variations in PV anatomy and insertion in the left atrium were observed. Narrowing of PV ostia after radiofrequency catheter ablation did not produce significant hemodynamic changes.

MR flow mapping of dobutamine-induced changes in diastolic heart function.

Abstract: Purpose To evaluate the ability of MR flow mapping to measure changes in left ventricular filling during β-adrenergic stimulation. Materials and Methods Mitral flow was measured in 10 healthy volunteers using conventional free breathing fast-field echo (FFE) with a spatial resolution of 2.7 × 2.2 mm and a temporal resolution of 22 msec. The sequence was repeated during dobutamine infusion (20 μg/kg/minute). Results Stroke volume increased from a median of 99 mL (range: 68–142 mL) (Note: values as presented are medians and ranges, throughout) to 114 mL (87–180 mL) (P < 0.05). Both early (E) peak filling rate (554 mL/second [433–497 mL] to 651 mL/second [496–1096 mL/second]) (P < 0.05) and atrial (A) peak filling rate (238 mL/second [183–352 mL/second] to 341 mL/second [230–538 mL/second]) (P < 0.05) increased. These changes, together with the increase in E acceleration peak and A deceleration peak, were consistent with facilitated myocardial relaxation. Conclusion Conventional free breathing FFE has the ability to measure the effects of β-adrenergic stimulation on left ventricular filling. J. Magn. Reson. Imaging 2004;19:176–181. © 2004 Wiley-Liss, Inc.

Six-months of recombinant human GH therapy in patients with ischemic cardiac failure

Abstract: Growth hormone therapy in patients with idiopathic dilated cardiomyopathy and ischemic cardiac failure has revealed varying effects on systolic function, probably related to the response in serum insulin-like growth factor I (IGF-I) levels. As diastolic function has not been studied thoroughly, we studied the effects of 6 months of recombinant human growth hormone (rh GH) treatment on systolic and diastolic function in patients with ischemic cardiac failure, using cardiovascular magnetic resonance (MR) imaging. Nineteen patients with ischemic cardiac failure (left ventricular ejection fraction (LVEF), <40%) were studied in a randomized trial. Nine patients received 6 months treatment with growth hormone (2 IU/day). Systolic and diastolic function were assessed at baseline and after 26 weeks by cardiovascular MR imaging. No differences were found in systolic and diastolic function between rh GH treated patients and controls. No change was observed in left ventricular mass index (LVMI), end-diastolic volume, end-systolic-volume and ejection fraction. The treated patients showed no clinical improvement. Six months of treatment with growth hormone therapy in ischemic cardiac failure has no favorable effects on LVMI, on systolic and diastolic function.

Hypertensive stress increases dispersion of repolarization

Abstract: Several electrocardiographic indices for repolarization heterogeneity have been proposed previously. The behavior of these indices under two different stressors at the same heart rate (i.e., normotensive gravitational stress, and hypertensive isometric stress) was studied. ECG and blood pressure were recorded in 56 healthy men during rest (sitting with horizontal legs), hypertensive stress (performing handgrip), and normotensive stress (sitting with lowered legs). During both stressors, heart rates differed <10% in 41 subjects, who constituted the final study group. Heart rate increased from 63 +/- 9 beats/min at rest to 71 +/- 11 beats/min during normotensive, and to 71 +/- 10 beats/min during hypertensive stress (P < 0.001). Systolic blood pressure was 122 +/- 15 mmHg at rest and 121 +/- 15 mmHg during normotensive stress, and increased to 151 +/- 17 mmHg during hypertensive stress (P < 0.001). The QT interval was larger during hypertensive (405 +/- 27) than during normotensive stress (389 +/- 26, P < 0.001). QT dispersion did not differ significantly between the two stressors. The mean interval between the apex and the end of the T wave (Tapex-Tend) of the mid-precordial leads was larger during hypertensive (121 +/- 17 ms) than during normotensive stress (116 +/- 15 ms, P < 0.001). The singular value decomposition T wave index was larger during hypertensive (0.144 +/- 0.071) than during normotensive stress (0.089 +/- 0.053, P < 0.001). Most indices of repolarization heterogeneity were larger during hypertensive stress than during normotensive stress. Hypertensive stressors are associated with arrhythmogeneity in vulnerable hearts. This may in part be explained by the induction of repolarization heterogeneity by hypertensive stress.

Coronary stent imaging with multidetector row computed tomography.

Abstract: Multidetector row Computed Tomography (MDCT) is developing rapidly as a potential non-invasive imaging method for the direct visualization of coronary arteries in patients presenting with suspected coronary artery disease. Recent technical improvements have led to improved spatial and temporal resolution and may even allow evaluation of coronary stents, which has remained difficult due to the small diameter and radio-opaque material. We describe two cases, a 65- and a 72-year old patient. Both patients had previously undergone percutaneous transluminal coronary angioplasty in combination with stent placement and were re-admitted to our hospital with recurrent angina. MDCT was performed prior to or after coronary angiography in order to assess stent patency non-invasively.

Dynamic Multislice Computed Tomography of Left Ventricular Function

Abstract: A 56-year-old man (known to have hypercholesterolemia) was hospitalized with signs of an acute inferior myocardial infarction, as evidenced by typical chest pain lasting for 2 hours and typical ECG changes (ST-T-segment elevation in leads II, III, AvF; no Q-wave formation). Plasma levels of cardiac enzymes (including troponins) were not yet elevated. On the basis of these findings, he was treated by thrombolysis (streptokinase), with relief of chest pain and normalization of ST-T segments. During hospitalization, he experienced an episode of heart failure with dyspnea at rest. Chest x-ray demonstrated pulmonary edema. Treatment with intravenous diuretics and inotropic agents was initiated with adequate response. Resting 2D echocardiography demonstrated an enlarged left ventricle with a resting left ventricular ejection fraction of 35%, …

Transcardiac conductance for continuous measurement of left ventricular volume: validation vs. angiography in patients.

Abstract: To test the feasibility of the transcardiac conductance (TCC) method for continuous, on-line measurement of absolute left ventricular (LV) volume and to validate the method by comparison with biplane angiography. Prospective clinical feasibility and validation study in a cardiac catheterization laboratory in a university hospital. Ten patients scheduled for electrophysiological studies (n=5), percutaneous transluminal coronary angioplasty (n=3), and left- and right-sided cardiac catheterization (n=2) were enrolled in the feasibility study. Twenty patients scheduled for diagnostic left- and right-sided cardiac catheterization were included in the validation study. The latter were studied at baseline and during right atrial pacing 30 beats/min above baseline. In the feasibility study satisfactory ventricular volume signals were obtained by TCC in eight of ten patients. In the validation study calibration factors (α and Vp) for TCC were obtained by thermodilution and hypertonic saline dilution, to yield absolute LV volume. Results indicate a good linear correlation with angiographic volume (R 2=0.78) with an intercept of 10±15 ml, not significantly different from 0 and slope of 1.17±0.16. Mean calibration factors α and Vp were 0.017±0.002 (interpatient variability 0.018) and 75.1±0.4 ml (interpatient variability 35.4 ml), respectively. The TCC method provides on-line and continuous LV volume signals in patients in a relatively noninvasive way. Calibration yields absolute LV volumes with a good linear correlation in comparison to biplane LV angiography. TCC appears to be a promising methodology for monitoring absolute LV volume in the ICU.

Cyclic Appropriate Mode Switching and Inappropriate Back Switching of a Biventricular Pacemaker During Atrial Tachyarrhythmia

Abstract: In patients with resynchronization devices and intact intrinsic AV conduction, atrial tachyarrhythmias may give rise to high ventricular rates, resulting in inhibition of (bi)ventricular pacing and concomitant lack of therapeutic effects of the device. This report presents a patient with atrial arrhythmias in whom mode switching and back switching of the biventricular pacemaker occurred, due to special timing of the atrial and ventricular deflections. This case report stresses the importance of strenuous treatment of atrial arrhythmias in patients with resynchronization devices.