Direct current cardioversion-triggered atypical Tako-tsubo cardiomyopathy: a case report and review of literature.

Background: Tako-tsubo stress cardiomyopathy is a clinical syndrome marked by transient reduction of left ventricular function in the setting of emotional or physical stress and in the absence of obstructive coronary artery disease. We describe a case of an atypical variant of Tako-tsubo in a male patient following an elective direct current cardioversion (DCCV). Case summary: A 78-year-old male whose atrial fibrillation persisted after earlier unsuccessful direct current DCCV and radiofrequency ablations presented to the emergency department for acutely worsening dyspnoea and orthopnoea 12 h following his most recent DCCV. Previously, he was known to have non-obstructive coronary artery disease. Evaluation was notable for troponin I 0.019 ng/mL (negative <0.050 ng/mL), pro-brain natriuretic peptide 2321 pg/mL (reference range 0.0-900 pg/mL). There were no acute electrocardiogram abnormalities. He required bilevel positive airway pressure but was weaned off eventually to room air. Transthoracic echocardiogram revealed newly reduced left ventricular ejection fraction of 45-50%, associated with hypokinesis of the basal anteroseptal segment, as well as akinesis of mid-inferoseptal and mid-anteroseptal segments. Apical contractility was preserved. On Day 5 of hospitalization, diagnostic left heart catheterization again revealed benign coronary anatomy, and he was discharged home the following day. Discussion: Only five other cases of cardioversion mediated Tako-tsubo cardiomyopathy have been reported in the literature. To our knowledge, this is the first case of DCCV-induced atypical Tako-tsubo cardiomyopathy. Although overall prognosis is favourable, some have been observed to require advanced support therapy. Given risk for life-threatening complications, patients undergoing cardioversion should be educated on symptoms of congestive cardiomyopathy.

Enhanced External Counterpulsation Therapy: Past, Present, and Future.

External counterpulsation therapy was first developed over half a century ago as a resuscitative tool to support the failing heart and was based on hemodynamic principles of the intraaortic balloon pump. Over the course of last few decades, it has evolved into the modern enhanced external counterpulsation (EECP) therapy, which has proven to be a safe, effective, and low-cost noninvasive treatment for patients with debilitating angina and chronic heart failure who are poor candidates for revascularization procedures and have suboptimal results from other therapies. Numerous studies have shown EECP to be efficacious in patients with chronic angina, with its effects lasting for several years after completion of therapy. Besides being safe in patients with coexisting left ventricular dysfunction, there is emerging evidence that EECP therapy may result in improvement in exercise capacity and oxygen consumption in heart failure patients. Several mechanisms have been postulated to explain the therapeutic effects of EECP, including improvement in endothelial function, promotion of angiogenesis and new collaterals, reduction in atherosclerotic burden, improvement in ventricular function, and peripheral training effects analogous to that of exercise. With greater understanding of these complex mechanisms, possible applications of EECP have broadened in recent years, with its use being studied in conditions like hepatorenal syndrome, erectile dysfunction, and restless leg syndrome. This review article offers a historical perspective on the origins of EECP, an overview of our current understanding of its physiological effects, and a glimpse at its future utilization in clinical practice.

Lipid effects of switching from prescription EPA+DHA (omega-3-acid ethyl esters) to prescription EPA only (icosapent ethyl) in dyslipidemic patients.

OBJECTIVES: Residual cardiovascular risk and persistently elevated triglycerides (TGs) may remain despite statin therapy in patients with dyslipidemia. Prescription omega-3 fatty acid formulations containing docosahexaenoic acid (DHA) and/or eicosapentaenoic acid (EPA) have been shown to reduce TGs and may potentially lower residual cardiovascular risk. However, DHA may raise low-density lipoprotein cholesterol (LDL-C) and compromise treatment goals. Icosapent ethyl (Vascepa®), a high-purity prescription EPA formulation, has been shown to lower TGs and other lipid parameters without raising LDL-C. There are no prospective, randomized, controlled trials of the effects of switching patients from omega-3-acid ethyl esters (Lovaza®), a prescription formulation containing EPA+DHA, to icosapent ethyl. METHODS: This retrospective chart review included records of high-risk patients aged ≥18 years receiving stable statin therapy for dyslipidemia who had been switched from prescription omega-3-acid ethyl esters 4 g/day to prescription icosapent ethyl 4 g/day and had available laboratory lipid profiles after receiving each for ≥2 months. Lipid assessments were conducted by local laboratories. Patient records were excluded if there were changes in medication or health condition that could affect lipid parameters. RESULTS: The records of 8 patients (6 women and 2 men; 54-83 years) met eligibility criteria. Following the switch to icosapent ethyl, LDL-C changes ranged from +3.2% to -69.1% (reduced in 7 patients), total cholesterol was reduced in all patients (-3.5% to -44.3%), and TG changes ranged from +32.4% to -59.0% (reduced in 6 patients). Decreases or no changes in non-high-density lipoprotein cholesterol were observed; changes in high-density lipoprotein cholesterol varied. No adverse events related to either product were reported. CONCLUSION: In this real-world retrospective analysis, switching high-risk statin-treated patients from omega-3-acid ethyl esters to icosapent ethyl resulted in favorable lipid changes. The analysis was limited by the small patient numbers, but lipid results were consistent with randomized controlled trials and previous case series.

Effects of enhanced external counterpulsation on stress radionuclide coronary perfusion and exercise capacity in chronic stable angina pectoris.

Enhanced external counterpulsation (EECP) is an effective noninvasive treatment for patients with coronary artery disease (CAD). EECP has been demonstrated to improve anginal class and time to ST-segment depression during exercise stress testing. This study assesses the efficacy of EECP in improving stress-induced myocardial ischemia using radionuclide perfusion treadmill stress tests (RPSTs). The international study group enrolled patients from 7 centers with chronic stable angina pectoris and a baseline ischemic pre-EECP RPST. Patients' demographic and clinical characteristics were recorded. A baseline pre-EECP maximal RPST was performed within 1 month before EECP treatment. The results were compared with a follow-up RPST performed within 6 months of completion of a 35-hour course of EECP. Four centers performed post-EECP RPST to the same level of exercise as pre-EECP, whereas 3 centers performed maximal RPST post-EECP. The study enrolled 175 patients (155 men and 20 women). Improvement in angina, defined by > or =1 Canadian Cardiovascular Society angina class change, was reported in 85% of patients. In the centers performing the same level of exercise, 81 of 97 patients (83%) had significant improvement in RPST perfusion images. Patients who underwent maximal RPST revealed improvement in exercise duration (6.61 +/- 1.88 pre-EECP vs 7.41 +/- 2.03 minutes post-EECP, p <0.0001); 42 of the 78 patients (54%) in this group showed significant improvement in RPST perfusion images. Thus, EECP was effective in improving stress myocardial perfusion in patients with chronic stable angina at both comparable (baseline) and at maximal exercise levels.