Phosphodiesterase 5 Inhibitor Use in Men With Hypertrophic Cardiomyopathy

The prevalence of sexual dysfunction (SD) in men with hypertrophic cardiomyopathy (HC) remains unknown, yet its clinical relevance may be high given that its treatment-phosphodiesterase 5 inhibitors (PDE5i)-can increase the left ventricular outflow tract pressure gradient. In this retrospective study, we evaluated the medical records of consecutively seen men with HC for the evidence of SD (defined as SD diagnosis noted in the medical record, the use of medications unique for SD, or SD reported by the patient on a routine clinical questionnaire). Of the 283 consecutively seen men with HC (mean age 52.9 ± 14.1 years), 63 patients (22%) with SD were identified. Of those with SD, 38% were recorded as regularly using PDE5i. In conclusion, SD and the use of PDE5i present a relatively common occurrence in men with HC, and further studies are needed to develop an evidence-guided algorithm for safe implementation of SD therapies in this most common inherited cardiomyopathy.

Correlation of geomagnetic activity with implantable cardioverter defibrillator shocks and antitachycardia pacing

OBJECTIVE

To investigate a potential relationship between implantable cardioverter defibrillator (ICD) therapies and daily geomagnetic activity (GMA) recorded in a large database.

PATIENTS AND METHODS

The ALTITUDE database, derived from the Boston Scientific LATITUDE remote monitoring system, was retrospectively analyzed for the frequency of ICD therapies. Daily GMA was expressed as the planetary K-index and the integrated A-index and was graded as levels I (quiet), II (unsettled), III (active), and IV (storm).

RESULTS

A daily mean ± SD of 59,468±11,397 patients were monitored between January 1, 2009, and May 15, 2012. The distribution of days according to GMA was as follows: level I, 924/1231 (75%); level II, 226/1231 (18%); level III, 60/1231 (5%); and level IV, 21/1231 (2%). The daily mean ± SD numbers of ICD shocks received per 1000 active patients in the database were 1.29±0.47, 1.17±0.46, 1.03±0.37, and 0.94±0.29 on level I, II, III, and IV days, respectively; the daily mean ± SD sums of shocks and antitachycardia pacing therapies were 9.29±2.86, 8.46±2.45, 7.92±1.80, and 7.83±2.28 on quiet, unsettled, active, and storm days, respectively. A significant inverse relationship between GMA and frequency of ICD therapies was identified, with the most pronounced difference between level I and level IV days (P<.001 for shocks; P=.008 for shocks + antitachycardia pacing).

CONCLUSION

In a large-scale cohort analysis, ICD therapies were delivered less frequently on days of higher GMA, confirming the previous pilot data and suggesting that higher GMA does not pose an increased risk of arrhythmias using ICD therapies as a surrogate marker. Further studies are needed to gain an in-depth understanding of the underlying mechanisms.

Relation of chronic obstructive pulmonary disease to atrial and ventricular arrhythmias

Chronic obstructive pulmonary disease (COPD) is associated with increased cardiovascular morbidity and mortality, yet the exact pathophysiological links remain unclear. Whether the presence and severity of COPD are associated with atrial or ventricular arrhythmias recorded on continuous electrocardiographic monitoring is unknown. We identified consecutive adult patients who underwent clinically indicated pulmonary function testing as well as 24-hour Holter monitoring at the Mayo Clinic, Rochester, from 2000 to 2009. Demographic data and relevant co-morbidities were gathered from the electronic medical record; severity of COPD was classified according to the GOLD classification, and arrhythmias were classified in concordance with the current clinical guidelines. From 7,441 patients who were included (age 64±16 years, 49% woman, 92% Caucasian), COPD was diagnosed in 3,121 (41.9%). Compared with those without COPD, the presence and severity of COPD were associated with increased likelihood of atrial fibrillation/atrial flutter (AF/AFL; 23.3% vs 11.0%, respectively, p<0.0001), nonsustained ventricular tachycardia (NSVT; 13.0% vs 5.9%, respectively, p<0.0001), and sustained ventricular tachycardia (0.9% vs 1.6%, respectively, p<0.0001). COPD remained a significant predictor of AF/AFL and NSVT (p<0.0001 and p<0.0001, respectively) after adjusting for age, gender, tobacco use, obesity, hypertension, coronary artery disease, heart failure, diabetes, anemia, cancer, chronic kidney disease, and rate/rhythm control medications. In conclusion, the independent association between the presence and severity of COPD and arrhythmias (AF/AFL and NSVT) provides further insight into the markedly increased cardiovascular mortality of patients with COPD. Further studies should explore which anti-arrhythmic strategies would best apply to the patients with COPD.