Kazumasa Adachi

Onset heart rate of microvolt-level T-wave alternans provides clinical and prognostic value in nonischemic dilated cardiomyopathy.

OBJECTIVES This study was designed to determine the prognostic value of onset heart rate (OHR) in T-wave alternans (TWA) in patients with nonischemic dilated cardiomyopathy (DCM). BACKGROUND One of the current major issues in DCM is to prevent sudden cardiac death (SCD). However, the value of the OHR of TWA as a prognostic indicator in DCM remains to be elucidated. METHODS We prospectively investigated 104 patients with DCM undergoing TWA testing. The end point of this study was defined as SCD, documented sustained ventricular tachycardia/ventricular fibrillation. Relations between clinical parameters and subsequent outcome were evaluated. RESULTS Forty-six patients presenting with TWA were assigned to one of the following two subgroups according to OHR for TWA of < or = 100 beats/min: group A (n = 24) with OHR < or = 100 beats/min and group B (n = 22) with 100 < OHR < or = 110 beats/min. T-wave alternans was negative in 37 patients (group C) and indeterminate in 21 patients. The follow-up result comprised 83 patients with determined TWA. During a follow-up duration of 21 +/- 14 months, there was a total of 12 arrhythmic events, nine of which included three SCDs in group A, two in group B and one in group C. The forward stepwise multivariate Cox hazard analysis revealed that TWA with an OHR < or = 100 beats/min and left ventricular ejection fraction were independent predictors of these arrhythmic events (p = 0.0001 and p = 0.0152, respectively). CONCLUSIONS The OHR of TWA is of additional prognostic value in DCM.

Determinant of microvolt-level T-wave alternans in patients with dilated cardiomyopathy

OBJECTIVES The aim of this study was to clarify the clinical significance and the determinant of microvolt-level T-wave alternans (TWA) in patients with dilated cardiomyopathy (DCM). BACKGROUND The prevention of sudden death in patients with DCM remains the therapeutic target. T-wave alternans has been proposed as a powerful tool for identification of patients at high risk for ventricular arrhythmias and sudden death in coronary artery disease. METHODS In 58 DCM patients, TWA was measured during bicycle exercise testing using a CH 2000 system (Cambridge Heart, Bedford, Massachusetts). The New York Heart Association class, signal-averaged electrocardiogram, QT dispersion, left ventricular end-diastolic diameter (LVDd) and percent fractional shortening detected by echocardiogram and the grade of the ventricular arrhythmia were obtained in all patients. RESULTS T-wave alternans was positive in 23 patients (TWA+ group), negative in 25 (TWA- group) and indeterminate in 10. Univariate analysis showed that the percentage of patients with ventricular tachycardia (VT) and the LVDd in the TWA+ group was significantly higher than those in the TWA- group (61% vs. 8%, p < 0.001 and 65 +/- 11 mm vs. 58 +/- 8 mm, p < 0.05, respectively). The sensitivity, specificity and predictive accuracy of TWA for VT were 88%, 72% and 77%, respectively. Multivariate analysis showed that the presence of VT was a major independent determinant of TWA in patients with DCM (p = 0.003). CONCLUSIONS T-wave alternans was closely related to VT in patients with DCM. T-wave alternans is a useful noninvasive test for identifying high risk patients with DCM who have VT.

A case of coronary lesion with lotus root appearance treated by percutaneous coronary intervention with intravascular ultrasound guidance

A 66-year-old man underwent percutaneous coronary intervention (PCI). Coronary angiography showed a diffuse lesion with lotus root appearance and severe stenosis in the left anterior descending artery (LAD). Multiple channels were observed by intravascular ultrasound (IVUS). Different channels were connected to the first diagonal branch, the first septal branch and LAD lumen separately. To prevent obstruction of side branches, we made connections to the branches from the main channel of LAD with tapered-tip guide wire, followed by balloon dilatation and stenting without side branch obstruction. IVUS findings were helpful for the PCI with a lotus root appearance lesion.

Percutaneous interventional techniques to remove embolized silicone port catheters from heart and great vessels

Rupture of a silicon port catheter is a relatively rare complication and sometimes it is difficult to remove it. We experienced three cases of retrieval of silicone port catheters migrating into cardiac ventricle or pulmonary artery. Several devices such as a snare wire, an ablation catheter, and a basket catheter in combination with interventional guiding catheter were applied to retrieve them. These interventional techniques are applicable for retrieval of embolized vascular access port system and other catheter fragments.

Implant Characteristics of Quadripolar and Bipolar Left Ventricular Leads for Cardiac Resynchronization Therapy: Results from the Attain Success Japan Study

Several studies have reported that the left ventricular (LV) lead implant success rate ranges between 88.0% and 92.4%. Coronary venous anatomy differs among patients thus, necessitating multiple types of leads. To date, the implant success rate among Japanese patients utilizing a pre-specified family LV leads (including bipolar and quadripolar) is not well known. The Attain Success Japan Study enrolled patients indicated for a de novo or an upgrade cardiac resynchronization therapy implant. Patients were followed for 3 months, and the implant success rates with Medtronic Attain family LV leads as well as the incidence of complications related to the LV lead were evaluated.Three hundred 53 patients were enrolled from 29 sites in Japan; 346 patients had LV lead implant attempts. The LV lead was successfully implanted in 336 patients (97.1%). Bipolar and quadripolar LV lead implants were successful in 97.2% and 99.2% of patients, respectively (P = 0.43). Four complications (1.2%) related to the LV leads were reported; all of which occurred in patients receiving bipolar LV leads. The quadripolar LV leads were more frequently implanted in the apical segment compared with bipolar leads (21.6% versus 3.8%, P < 0.01). This study demonstrated a high implant success rate and a low LV lead-related complication rate, regardless of bipolar, or quadripolar in a Japanese cohort of patients.

Familial Carney complex with biatrial cardiac myxoma

We report a case of Carney complex (CNC) with biatrial cardiac myxoma. The patient had left and right atrial myxomas which were resected in a surgery. She showed bilateral adrenal tumors and multiple mammary tumors. She had pigmentation on her lower lip. Previously, her daughter was also diagnosed with CNC with cardiac myxoma. Both of them showed mutations in the PRKAR1A gene. <Learning objective: Carney complex is a syndrome with skin pigmentation, myxomas, and endocrine abnormalities. It is an autosomal dominant disease and shows PRKAR1A gene mutation. We experienced a rare case of familial Carney complex with biatrial cardiac myoxomas found by echocardiography and treated surgically.>