Secondary mitral regurgitation: percutaneous edge-to-edge repair on the cutting edge?

PURPOSE OF REVIEW: Secondary mitral regurgitation commonly complicates heart failure. Although the evidence for its management is most robust for treating the underlying cardiomyopathy, treatment aimed at additionally reducing the severity of mitral regurgitation with a percutaneous edge-to-edge device, MitraClip, has recently emerged. RECENT FINDINGS: Despite the use of contemporary evidence-based heart failure therapies, patients with secondary mitral regurgitation and heart failure continue to remain at high risk for adverse clinical events; in both the MITRA-FR and COAPT trials, an extremely high event rate was evident in the medically managed arms over the respective 12-24-month follow-up. Data supporting the use of MitraClip to mitigate adverse outcomes in secondary mitral regurgitation is, however, conflicting. In MITRA-FR no difference was noted between MitraClip compared with the medically managed arm for the composite of all-cause death or heart failure hospitalization at 12 months. However, in COAPT, a significant reduction in the rate of heart failure re-hospitalization over 2 years was evident with MitraClip compared with medical therapy alone. SUMMARY: Recommendations exist for the use of MitraClip in patients with primary mitral regurgitation and prohibitive surgical risk. However, with the divergent results of two recent high-quality randomized trials, its role in patients with secondary mitral regurgitation remains controversial.

Right ventricular pacing is associated with increased rates of appropriate implantable cardioverter defibrillator shocks.

BACKGROUND: Right ventricular (RV) pacing has been associated with increased risk of pacemaker-induced cardiomyopathy, hospitalization and death among patients with implantable cardioverter defibrillators (ICDs). Little is known about its association with ventricular tachyarrhythmias. We hypothesize that RV pacing is associated with increased incidence of appropriate ICD shocks and death. METHODS: Retrospective study of consecutive patients with de novo ICD insertion (excluding cardiac resynchronization therapy devices) from a single tertiary care center. Patients were classified into <10% RV pacing (low-pace group) and ≥10% RV pacing (high-pace group). Data were compared using two-tailed t tests and Fisher's exact test. Binomial logistic regression was performed to identify predictors of appropriate ICD therapies. RESULTS: A total of 178 patients (54 high paced and 124 low paced) were included. Mean follow-up was 43 ± 11 months. Appropriate shocks occurred in 27 patients (15%) and were significantly higher in the high-pace group (35% vs. 10%, p = 0.008), as the number of deaths (31% vs. 11%, p = 0.001). Binary logistic regression showed a significantly increased risk of shock (OR 2.99, p = 0.01) and death (OR 3.61, p = 0.002) in high-paced patients. Multivariable analysis showed no difference in risk of shocks based on age, sex or ejection fraction. Older patients had higher risk of death. CONCLUSIONS: In this population of ICD patients, those with a high prevalence of RV pacing experienced more shocks for VF/VT and had higher mortality. Further studies should be done to determine whether minimizing RV pacing reduces arrhythmias, shock burden and death in patients with ICDs.

Incidental Acute ST Elevation Due to Cannabis-Induced Myocarditis After a Mechanical Fall.

We present the case of a young male with an orthopedic injury after a mechanical fall, who developed atypical chest pain associated with ST elevation and elevated biomarkers suggestive of myocardial injury. He was found to have myocarditis on cardiac magnetic resonance imaging that we postulate was secondary to inhalation of marijuana. Cannabis-induced myocarditis and its potential complications are a health hazard that is bound to grow with the legalization of marijuana use in many countries.

Nous présentons ici le cas d'un jeune homme souffrant d'une lésion orthopédique subie après une chute mécanique, qui a développé une douleur thoracique atypique associée à une élévation du segment ST et à des biomarqueurs élevés évocateurs d'une lésion myocardique. L'imagerie par résonance magnétique cardiaque a révélé qu'il souffrait d'une myocardite que nous supposons être consécutive à l'inhalation de marijuana. La myocardite induite par le cannabis et ses complications potentielles constituent un risque pour la santé qui ne peut que croître avec la légalisation de l'usage de la marijuana dans de nombreux pays.