Heart rate recovery after exercise and long-term prognosis in patients with coronary artery disease

Background

The long-term prognostic value of heart rate recovery (HRR) has been incompletely documented in patients with coronary artery disease (CAD). We sought to confirm the prognostic value of HRR in a large cohort with stable CAD.

Methods

From the Coronary Artery Surgery Study registry, a database of 24,958 patients with CAD who underwent cardiac catheterization between 1974 and 1979, we identified 4097 patients with baseline exercise stress testing data. HRR was measured at 3 minutes post exercise during a passive recovery. Clinical outcomes were evaluated according to HRR in both threshold and continuous models.

Results

Median long-term follow-up was 14.7 years (interquartile range, 9.8-16.2). HRR < 46 beats per minute (Bpm) most appropriately differentiated nonsurvivors from survivors (area under receiver operating characteristic curve = 0.613) and was associated with an increased risk of all-cause death (adjusted hazard ratio = 1.15; P = 0.011). Increasing HRR was associated with a lower risk of all-cause (adjusted hazard ratio = 0.94 per 10 Bpm; 95% confidence interval, 0.91-0.97; P = 0.0005) and cardiovascular (CV) mortality (adjusted hazard ratio = 0.94 per 10 Bpm; 95% confidence interval, 0.90-0.98; P = 0.003).

Conclusions

HRR at 3 minutes independently predicts long-term all-cause and CV mortality in patients with stable CAD. Measurement of HRR at 3 minutes during passive recovery can be used as a complementary tool to identify patients with a higher total and CV risk.     

A Randomized Study of Defibrillator Lead Implantations in the Right Ventricular Mid-Septum versus the Apex: The SEPTAL Study(τ)

Impact of Recalls on ICD Utilization . Introduction: The study was designed to evaluate the feasibility and performance of right ventricular (RV) mid‐septal versus apical implantable defibrillator (ICD) lead placement. Methods and Results: SEPTAL is a randomized, noninferiority trial, which randomly assigned patients to implantation of ICD leads in the RV mid‐septum versus apex, with a primary objective of comparing the implant success rate of implant at each site, based on strict electrical predefined criteria. We also compared the (1) pacing lead characteristics, (2) rates of appropriate and inappropriate ICD therapies, and (3) all‐cause mortality between the 2 sites at 1 year. The trial enrolled 215 patients (mean age = 59.7 ± 12.4 years, mean LVEF = 34.0 ± 14.2%, 84.2% men), of whom 148 (68.8%) presented with ischemic heart disease. The ICD indication was primary prevention in 117 patients (54.4%). The lead was successfully implanted in 96/107 patients (89.7%) assigned to the RV mid‐septum, and in 99/108 (91.7%) assigned to the apex (ns). The 1‐year rate of lead‐related adverse events was similar in both groups. A total of 8 first inappropriate ICD therapies (7.9%) were delivered in the RV mid‐septal group, versus 8 (7.8%) in the apical group (ns), while first appropriate therapies were delivered to 22 (21.4%) and 24 patients (23.8%), respectively (ns). All‐cause mortality was 7.9% in the RV mid‐septal versus 2.9% in the RV apical group (ns). Conclusion: This study confirmed the technical feasibility and noninferior performance of ICD leads implanted in the RV mid‐septum versus the apex. (J Cardiovasc Electrophysiol, Vol. 23, pp. 853‐860, August 2012)     

Regression of Atherosclerosis

Atherosclerotic cardiovascular disease (CVD) is a complex disorder that leads to premature death and hospitalization. Several drugs have been, or are currently being tested for their ability to reduce cardiovascular mortality and/or promote regression of atherosclerotic lesions. In addition to "hard end point" clinical trials in which total and cardiovascular mortality as well as risk of incident myocardial infarction are considered as outcomes, trials with surrogate end points using imaging biomarkers can rapidly assess the efficacy of new cardiovascular drugs. Low-density lipoprotein-based therapies with statins have been shown to promote atherosclerosis regression, and several other drugs targeting high-density lipoproteins or inflammation/oxidation are currently being tested in both outcomes and imaging trials in which atherosclerosis regression is anticipated. In this review, we focus on the latest progress in CVD and highlight novel drugs that tackle atherosclerosis as well as the currently used and upcoming imaging techniques to optimally measure atherosclerosis progression.