Sick sinus syndrome concomitant with myopathy associated with anti-mitochondrial antibodies: a case report.

Background: Anti-mitochondrial antibody (AMA)-associated myopathy is known to be concomitant with primary biliary cirrhosis and to cause both skeletal muscle disorders and arrhythmias, myocardium disorders, and respiratory muscle disorders. We report a case of AMA-associated myopathy in which the bradycardia-related symptoms preceded the skeletal muscle symptoms. Case summary: A 59-year-old woman visited the emergency room in our hospital following a syncopal event. The patient was bradycardiac (45 b.p.m.) with a junctional rhythm resulting from sick sinus syndrome (SSS) and was suffering from heart failure. Blood tests revealed elevated creatine kinase (CK) and hepatic enzymes. She underwent permanent pacemaker implantation. However, it proved difficult to detect the electrical potential in the right atrium. Although successful atrial pacing was achieved at the lower right atrial septum, the atrial threshold was markedly high and she depended on ventricular pacing. One year later, neurological examination and muscle biopsy confirmed the diagnosis of AMA-associated myopathy. Following this diagnosis, steroid pulse therapy was initiated. Steroid administration relieved her symptoms and lowered the CK levels but the atrial standstill persisted. The patient takes low-dose prednisolone and has had an uneventful course for 3 years. Discussion: To the best of our knowledge, this is the first case of AMA-associated myopathy diagnosed by the first symptom related to bradycardia due to SSS. Patients with AMA-associated myopathy can experience a variety of cardiac symptoms, including arrhythmias, and initially complain of cardiac symptoms without symptoms of skeletal myopathy. This disease should be considered when diagnosing patients with arrhythmia and elevated CK.

Prognostic predictors and echocardiographic time course after device replacement in patients treated chronically with cardiac resynchronization therapy devices.

The prognostic predictors of death or heart failure hospitalization and the echocardiographic response after initial cardiac resynchronization therapy (CRT) device replacement (CRT-r) remain unclear. We evaluated the predictors and the echocardiographic time course in patients after CRT-r. Consecutive 60 patients underwent CRT-r because of battery depletion. Patients were divided into two groups depending on the chronic echocardiographic response to CRT (left ventricular end-systolic volume [LVESV] reduction of ≥ 15%) at the time of CRT-r: CRT responders (group A; 35 patients) and CRT nonresponders (group B; 25 patients). The primary endpoint was a composite of death from any cause or heart failure hospitalization. Changes in LVESV and left ventricular ejection fraction (LVEF) after CRT-r were also analyzed. During the mean follow-up of 46 ± 33 months after CRT-r, the primary endpoint occurred more frequently in group B (group A versus group B; 8/35 [23%] patients versus 19/25 [76%] patients, p < 0.001). No significant changes in LVESV and LVEF were observed at the mean of 46 ± 29 months after CRT-r in both groups. A multivariate analysis identified echocardiographic nonresponse to CRT, chronic kidney disease, atrial fibrillation, and New York Heart Association functional class III or IV at the time of CRT-r as independent predictors of the primary endpoint in all patients. Residual echocardiographic nonresponse, comorbidities, and heart failure symptoms at the time of CRT-r predict the subsequent very long-term prognosis after CRT-r. No further echocardiographic response to CRT was found after CRT-r.

Pacemaker implantation using the SelectSecure system for a patient with persistent left superior vena cava and absent right superior vena cava: Insights into techniques for stable lead fixation.

The techniques for successful pacemaker implantation via the PLSVC with the SelectSecure system (Medtronic, Minneapolis, Minnesota, USA) are unknown. Regarding the techniques, we presented a case in which we implanted a pacemaker via the PLSVC in patient with absent RSVC using the SelectSecure system.

Heparin-induced thrombocytopenia associated with polycythemia vera during the treatment of acute coronary syndrome.

Here, we report a case of heparin-induced thrombocytopenia (HIT) associated with polycythemia vera (PV) during the treatment of acute coronary syndrome. An 84-year-old woman with pre-existing PV had an acute myocardial infarction and developed HIT after using heparin. An additional myocardial infarction was caused by HIT, and caused marked damage to her cardiac function. However, she was successfully treated with argatroban infusion and intensive care. In this case, we suspected HIT at an extremely early stage, when the decline in platelet count remained at 16%, which might have prevented further thrombosis. Subsequently, the nadir in the platelet count remained at 32%, which resulted in "intermediate possibility of HIT" according to the 4Ts score; thus, further detailed serological examination may be required for accurate diagnosis of HIT. .