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Archive for April, 2014

Journal Club 23 April 2014

Paper

A Randomized Trial to Assess Catheter Ablation Versus Rate Control in the Management of Persistent Atrial Fibrillation in Heart Failure

Presenter

PM

Summary

Objectives

This study sought to compare catheter ablation with rate control for persistent atrial fibrillation (AF) in heart fail- ure (HF).
Background The optimal therapy for AF in HF is unclear. Drug-based rhythm control has not proved clinically beneficial. Cath-
eter ablation improves cardiac function in patients with HF, but impact on physiological performance has not been formally evaluated in a randomized trial.

Methods

In a randomized, open-label, blinded-endpoint clinical trial, adults with symptomatic HF, radionuclide left ventric- ular ejection fraction (EF) Յ35%, and persistent AF were assigned to undergo catheter ablation or rate control. Primary outcome was 12-month change in peak oxygen consumption. Secondary endpoints were quality of life, B-type natriuretic peptide, 6-min walk distance, and EF. Results were analyzed by intention-to-treat.

Results

Fifty-two patients (age 63 Ϯ 9 years, EF 24 Ϯ 8%) were randomized, 26 each to ablation and rate control. At 12 months, 88% of ablation patients maintained sinus rhythm (single-procedure success 68%). Under rate control, rate criteria were achieved in 96%. The primary endpoint, peak oxygen consumption, significantly increased in the ablation arm compared with rate control (difference ϩ3.07 ml/kg/min, 95% confidence interval: 0.56 to 5.59, p ϭ 0.018). The change was not evident at 3 months (ϩ0.79 ml/kg/min, 95% confidence interval: Ϫ1.01 to 2.60, p ϭ 0.38). Ablation improved Minnesota score (p ϭ 0.019) and B-type natriuretic peptide (p ϭ 0.045) and showed nonsignificant trends toward improved 6-min walk distance (p ϭ 0.095) and EF (p ϭ 0.055).

Conclusions

This first randomized trial of ablation versus rate control to focus on objective exercise performance in AF and HF
shows significant benefit from ablation, a strategy that also improves symptoms and neurohormonal status. The ef- fects develop over 12 months, consistent with progressive amelioration of the HF syndrome.

Supplementary Material

The editorial is here.

Journal Club 16 April 2014

Paper

A Controlled Trial of Renal Denervation for Resistant Hypertension

Presenter

SP

Summary

BACKGROUND

Prior unblinded studies have suggested that catheter-based renal-artery denervation reduces blood pressure in patients with resistant hypertension.

METHODS

We designed a prospective, single-blind, randomized, sham-controlled trial. Patients with severe resistant hypertension were randomly assigned in a 2:1 ratio to undergo renal denervation or a sham procedure. Before randomization, patients were receiving a stable antihypertensive regimen involving maximally tolerated doses of at least three drugs, including a diuretic. The primary efficacy end point was the change in office systolic blood pressure at 6 months; a secondary efficacy end point was the change in mean 24-hour ambulatory systolic blood pressure. The primary safety end point was a composite of death, end-stage renal disease, embolic events resulting in end-organ damage, renovascular complications, or hypertensive crisis at 1 month or new renal-artery stenosis of more than 70% at 6 months.

RESULTS

A total of 535 patients underwent randomization. The mean (±SD) change in systolic blood pressure at 6 months was −14.13±23.93 mm Hg in the denervation group as compared with −11.74±25.94 mm Hg in the sham-procedure group (P<0.001 for both comparisons of the change from baseline), for a difference of −2.39 mm Hg (95% confidence interval [CI], −6.89 to 2.12; P=0.26 for superiority with a margin of 5 mm Hg). The change in 24-hour ambulatory systolic blood pressure was −6.75±15.11 mm Hg in the denervation group and −4.79±17.25 mm Hg in the sham-procedure group, for a difference of −1.96 mm Hg (95% CI, −4.97 to 1.06; P=0.98 for superiority with a margin of 2 mm Hg). There were no significant differences in safety between the two groups.

CONCLUSIONS

This blinded trial did not show a significant reduction of systolic blood pressure in patients with resistant hypertension 6 months after renal-artery denervation as compared with a sham control.

ACEI ARB Combination Alert

The European Medicines Agency has issued an alert regarding use of ACE inhbitors and Angiotensin Receptor blockers. It is available here.

Categories: Uncategorized

Journal Club 2 April 2014

Paper

Survival with Cardiac-Resynchronization Therapy in Mild Heart Failure

Presenter

MD

Summary

BACKGROUND

The Multicenter Automatic Defibrillator Implantation Trial with Cardiac Resynchro-nization Therapy (MADIT-CRT) showed that early intervention with cardiac-resyn-chronization therapy with a defibrillator (CRT-D) in patients with an electrocardio-graphic pattern showing left bundle-branch block was associated with a significant reduction in heart-failure events over a median follow-up of 2.4 years, as compared with defibrillator therapy alone.

METHODS

We evaluated the effect of CRT-D on long-term survival in the MADIT-CRT popula-tion. Post-trial follow-up over a median period of 5.6 years was assessed among all 1691 surviving patients (phase 1) and subsequently among 854 patients who were enrolled in post-trial registries (phase 2). All reported analyses were performed on an intention-to-treat basis.

RESULTS

At 7 years of follow-up after initial enrollment, the cumulative rate of death from any cause among patients with left bundle-branch block was 18% among patients ran-domly assigned to CRT-D, as compared with 29% among those randomly assigned to defibrillator therapy alone (adjusted hazard ratio in the CRT-D group, 0.59; 95% confidence interval [CI], 0.43 to 0.80; P<0.001). The long-term survival benefit of CRT-D in patients with left bundle-branch block did not differ significantly according to sex, cause of cardiomyopathy, or QRS duration. In contrast, CRT-D was not associ-ated with any clinical benefit and possibly with harm in patients without left bundle-branch block (adjusted hazard ratio for death from any cause, 1.57; 95% CI, 1.03 to 2.39; P = 0.04; P<0.001 for interaction of treatment with QRS morphologic findings).

CONCLUSIONS

Our findings indicate that in patients with mild heart-failure symptoms, left ventricular dysfunction, and left bundle-branch block, early intervention with CRT-D was associated with a significant long-term survival benefit.

Supplementary Material

Paper supplementary material
Editorial