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Journal ArticleDOI

Combined cardiac resynchronization and implantable cardioversion defibrillation in advanced chronic heart failure: the MIRACLE ICD Trial.

TL;DR: Cardiac resynchronization improved quality of life, functional status, and exercise capacity in patients with moderate to severe HF, a wide QRS interval, and life-threatening arrhythmias without proarrhythmia or compromised ICD function.
Abstract: ContextCardiac resynchronization therapy (CRT) through biventricular pacing is an effective treatment for heart failure (HF) with a wide QRS; however, the outcomes of patients requiring CRT and implantable cardioverter defibrillator (ICD) therapy are unknown.ObjectiveTo examine the efficacy and safety of combined CRT and ICD therapy in patients with New York Heart Association (NYHA) class III or IV congestive HF despite appropriate medical management.Design, Setting, and ParticipantsRandomized, double-blind, parallel-controlled trial conducted from October 1, 1999, to August 31, 2001, of 369 patients with left ventricular ejection fraction of 35% or less, QRS duration of 130 ms, at high risk of life-threatening ventricular arrhythmias, and in NYHA class III (n = 328) or IV (n = 41) despite optimized medical treatment.InterventionsOf 369 randomized patients who received devices with combined CRT and ICD capabilities, 182 were controls (ICD activated, CRT off) and 187 were in the CRT group (ICD activated, CRT on).Main Outcome MeasuresThe primary double-blind study end points were changes between baseline and 6 months in quality of life, functional class, and distance covered during a 6-minute walk. Additional outcome measures included changes in exercise capacity, plasma neurohormones, left ventricular function, and overall HF status. Survival, incidence of ventricular arrhythmias, and rates of hospitalization were also compared.ResultsAt 6 months, patients assigned to CRT had a greater improvement in median (95% confidence interval) quality of life score (–17.5 [–21 to –14] vs –11.0 [–16 to –7], P = .02) and functional class (–1 [–1 to –1] vs 0 [–1 to 0], P = .007) than controls but were no different in the change in distance walked in 6 minutes (55 m [44-79] vs 53 m [43-75], P = .36). Peak oxygen consumption increased by 1.1 mL/kg per minute (0.7-1.6) in the CRT group vs 0.1 mL/kg per minute (–0.1 to 0.8) in controls (P = .04), although treadmill exercise duration increased by 56 seconds (30-79) in the CRT group and decreased by 11 seconds (–55 to 12) in controls (P<.001). No significant differences were observed in changes in left ventricular size or function, overall HF status, survival, and rates of hospitalization. No proarrhythmia was observed and arrhythmia termination capabilities were not impaired.ConclusionsCardiac resynchronization improved quality of life, functional status, and exercise capacity in patients with moderate to severe HF, a wide QRS interval, and life-threatening arrhythmias. These improvements occurred in the context of underlying appropriate medical management without proarrhythmia or compromised ICD function.
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Journal ArticleDOI
14 Apr 2005
TL;DR: Cardiac resynchronization has been shown to reduce symptoms and improve left ventricular function in patients with heart failure due to systolic dysfunction and cardiac dyssynchrony.
Abstract: background Cardiac resynchronization reduces symptoms and improves left ventricular function in many patients with heart failure due to left ventricular systolic dysfunction and cardiac dyssynchrony We evaluated its effects on morbidity and mortality methods Patients with New York Heart Association class III or IV heart failure due to left ventricular systolic dysfunction and cardiac dyssynchrony who were receiving standard pharmacologic therapy were randomly assigned to receive medical therapy alone or with cardiac resynchronization The primary end point was the time to death from any cause or an unplanned hospitalization for a major cardiovascular event The principal secondary end point was death from any cause results A total of 813 patients were enrolled and followed for a mean of 294 months The primary end point was reached by 159 patients in the cardiac-resynchronization group, as compared with 224 patients in the medical-therapy group (39 percent vs 55 percent; hazard ratio, 063; 95 percent confidence interval, 051 to 077; P<0001) There were 82 deaths in the cardiac-resynchronization group, as compared with 120 in the medical-therapy group (20 percent vs 30 percent; hazard ratio 064; 95 percent confidence interval, 048 to 085; P<0002) As compared with medical therapy, cardiac resynchronization reduced the interventricular mechanical delay, the end-systolic volume index, and the area of the mitral regurgitant jet; increased the left ventricular ejection fraction; and improved symptoms and the quality of life (P<001 for all comparisons) conclusions In patients with heart failure and cardiac dyssynchrony, cardiac resynchronization improves symptoms and the quality of life and reduces complications and the risk of death These benefits are in addition to those afforded by standard pharmacologic therapy The implantation of a cardiac-resynchronization device should routinely be considered in such patients

5,493 citations

Journal ArticleDOI
TL;DR: This document summarizes current capabilities, research and operational priorities, and plans for further studies that were established at the 2015 USGS workshop on quantitative hazard assessments of earthquake-triggered landsliding and liquefaction.
Abstract: ![Figure][1] ![Figure][1] ![Figure][1] ![Figure][1] ![Figure][1] ![Figure][1] ![Figure][1] ![Figure][1] ![Figure][1] ![Figure][1] ![Figure][1] ![Figure][1] ![Figure][1

4,975 citations

Journal ArticleDOI
TL;DR: The American College of Cardiology (ACC)/American Heart Association (AHA) Task Force on Practice Guidelines regularly reviews existing guidelines to determine when an update or full revision is needed.

4,144 citations

Journal ArticleDOI
TL;DR: Theodore G. Feldman, MD, PhD, FACC, FAHA, Chair as mentioned in this paper, Chair, Chair of FAHA 2015, 2016, 2017, 2018, 2019, 2019
Abstract: Mariell Jessup, MD, FACC, FAHA, Chair [*][1] William T. Abraham, MD, FACC, FAHA[†][2] Donald E. Casey, MD, MPH, MBA[‡][3] Arthur M. Feldman, MD, PhD, FACC, FAHA[§][4] Gary S. Francis, MD, FACC, FAHA[§][4] Theodore G. Ganiats, MD[∥][5] Marvin A. Konstam, MD, FACC[¶][6] Donna M.

3,542 citations

References
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Journal ArticleDOI
TL;DR: In patients with a prior myocardial infarction and advanced left ventricular dysfunction, prophylactic implantation of a defibrillator improves survival and should be considered as a recommended therapy.
Abstract: Background Patients with reduced left ventricular function after myocardial infarction are at risk for life-threatening ventricular arrhythmias. This randomized trial was designed to evaluate the effect of an implantable defibrillator on survival in such patients. Methods Over the course of four years, we enrolled 1232 patients with a prior myocardial infarction and a left ventricular ejection fraction of 0.30 or less. Patients were randomly assigned in a 3:2 ratio to receive an implantable defibrillator (742 patients) or conventional medical therapy (490 patients). Invasive electrophysiological testing for risk stratification was not required. Death from any cause was the end point. Results The clinical characteristics at base line and the prevalence of medication use at the time of the last follow-up visit were similar in the two treatment groups. During an average follow-up of 20 months, the mortality rates were 19.8 percent in the conventional-therapy group and 14.2 percent in the defibrillator group....

6,175 citations

Journal ArticleDOI
TL;DR: In this article, a simple procedure for multiple tests of significance based on individual p-values is derived, which is sharper than Holm's (1979) sequentially rejective procedure.
Abstract: SUMMARY A simple procedure for multiple tests of significance based on individual p-values is derived. This simple procedure is sharper than Holm's (1979) sequentially rejective procedure. Both procedures contrast the ordered p-values with the same set of critical values. Holm's procedure rejects an hypothesis only if its p-value and each of the smaller p-values are less than their corresponding critical-values. The new procedure rejects all hypotheses with smaller or- equal p-values to that of any one found less than its critical value.

4,610 citations

Journal ArticleDOI
TL;DR: Cardiac resynchronization results in significant clinical improvement in patients who have moderate-to-severe heart failure and an intraventricular conduction delay.
Abstract: Background Previous studies have suggested that cardiac resynchronization achieved through atrial-synchronized biventricular pacing produces clinical benefits in patients with heart failure who have an intraventricular conduction delay. We conducted a double-blind trial to evaluate this therapeutic approach. Methods Four hundred fifty-three patients with moderate-to-severe symptoms of heart failure associated with an ejection fraction of 35 percent or less and a QRS interval of 130 msec or more were randomly assigned to a cardiac-resynchronization group (228 patients) or to a control group (225 patients) for six months, while conventional therapy for heart failure was maintained. The primary end points were the New York Heart Association functional class, quality of life, and the distance walked in six minutes. Results As compared with the control group, patients assigned to cardiac resynchronization experienced an improvement in the distance walked in six minutes (+39 vs. +10 m, P=0.005), functional clas...

4,329 citations

Journal ArticleDOI
TL;DR: In this article, transvenous atriobiventricular pacemakers (with leads in one atrium and each ventricle) were used to reduce ventricular asynchrony.
Abstract: BACKGROUND: One third of patients with chronic heart failure have electrocardiographic evidence of a major intraventricular conduction delay, which may worsen left ventricular systolic dysfunction through asynchronous ventricular contraction. Uncontrolled studies suggest that multisite biventricular pacing improves hemodynamics and well-being by reducing ventricular asynchrony. We assessed the clinical efficacy and safety of this new therapy. METHODS: Sixty-seven patients with severe heart failure (New York Heart Association class III) due to chronic left ventricular systolic dysfunction, with normal sinus rhythm and a duration of the QRS interval of more than 150 msec, received transvenous atriobiventricular pacemakers (with leads in one atrium and each ventricle). This single-blind, randomized, controlled crossover study compared the responses of the patients during two periods: a three-month period of inactive pacing (ventricular inhibited pacing at a basic rate of 40 bpm) and a three-month period of active (atriobiventricular) pacing. The primary end point was the distance walked in six minutes; the secondary end points were the quality of life as measured by questionnaire, peak oxygen consumption, hospitalizations related to heart failure, the patients' treatment preference (active vs. inactive pacing), and the mortality rate. RESULTS: Nine patients were withdrawn from the study before randomization, and 10 failed to complete both study periods. Thus, 48 patients completed both phases of the study. The mean distance walked in six minutes was 22 percent greater with active pacing (399+/-100 m vs. 326+/-134 m, P<0.001), the quality-of-life score improved by 32 percent (P<0.001), peak oxygen uptake increased by 8 percent (P<0.03), hospitalizations were decreased by two thirds (P<0.05), and active pacing was preferred by 85 percent of the patients (P<0.001). CONCLUSIONS: Although it is technically complex, atriobiventricular pacing significantly improves exercise tolerance and quality of life in patients with chronic heart failure and intraventricular conduction delay.

2,540 citations

Journal ArticleDOI
TL;DR: Cardiac resynchronization results in significant clinical improvement in patients who have moderate-to-severe heart failure and an intraventricular conduction delay.
Abstract: BACKGROUND Previous studies have suggested that cardiac resynchronization achieved through atrial-synchronized biventricular pacing produces clinical benefits in patients with heart failure who have an intraventricular conduction delay. We conducted a double-blind trial to evaluate this therapeutic approach. METHODS Four hundred fifty-three patients with moderate-to-severe symptoms of heart failure associated with an ejection fraction of 35 percent or less and a QRS interval of 130 msec or more were randomly assigned to a cardiac-resynchronization group (228 patients) or to a control group (225 patients) for six months, while conventional therapy for heart failure was maintained. The primary end points were the New York Heart Association functional class, quality of life, and the distance walked in six minutes. RESULTS As compared with the control group, patients assigned to cardiac resynchronization experienced an improvement in the distance walked in six minutes (+39 vs. +10 m, P=0.005), functional class (P<0.001), quality of life (-18.0 vs. -9.0 points, P= 0.001), time on the treadmill during exercise testing (+81 vs. +19 sec, P=0.001), and ejection fraction (+4.6 percent vs. -0.2 percent, P<0.001). In addition, fewer patients in the group assigned to cardiac resynchronization than control patients required hospitalization (8 percent vs. 15 percent) or intravenous medications (7 percent vs. 15 percent) for the treatment of heart failure (P<0.05 for both comparisons). Implantation of the device was unsuccessful in 8 percent of patients and was complicated by refractory hypotension, bradycardia, or asystole in four patients (two of whom died) and by perforation of the coronary sinus requiring pericardiocentesis in two others. CONCLUSIONS Cardiac resynchronization results in significant clinical improvement in patients who have moderate-to-severe heart failure and an intraventricular conduction delay.

2,332 citations


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