Landiolol, an intravenous ß1-selective blocker, is useful for dissociating a fusion of atrial activation via accessory pathway and atrioventricular node.

Introduction: During ventricular pacing, a fusion of atrial activation may occur owing to the simultaneous retrograde conduction of the atrioventricular (AV) node and accessory pathway (AP), potentially leading to an inaccurate mapping of the atrial AP insertion site. Objective: We tested the hypothesis that landiolol, an ultra-short-acting intravenous ß1-blocker, could dissociate a fusion of atrial activation. Methods: We conducted a prospective before-and-after study to investigate the effect of landiolol on retrograde conduction via the AV node and AP. We enrolled 21 consecutive patients with orthodromic AV reciprocating tachycardia who underwent electrophysiological studies at our hospital between January 1, 2018, and August 31, 2020. Results: Six patients exhibited a fusion of atrial activation. After landiolol administration (10 µg/kg/min), the effective refractory period was unchanged in AP (280 [240-290] ms vs. 280 [245-295] ms, p = .91), whereas that of the AV node was prolonged (275 [215-380] ms vs. 332 [278-445] ms, p = .03). The Wenckebach pacing rate via retrograde AV node decreased after landiolol administration (180 [140-200] beats per minute [bpm] vs. 140 [120-180] bpm, p = .02). Thus, landiolol decreased the minimum ventricular pacing rate required to dissociate a fusion of atrial activation (180 [160-200] bpm vs. 140 [128-155] bpm, p = .007). Radiofrequency catheter ablation under landiolol administration successfully eliminated AP in all patients during ventricular pacing without complications or recurrence. Conclusion: Landiolol inhibited the AV node without affecting the AP and helped dissociate a fusion of atrial activation at a lower ventricular pacing rate.

The usefulness of balloon occlusive left ventricular lead delivery in combination with the quadripolar active fixation lead for a patient with complex coronary venous morphology.

Complex coronary vein morphology impedes the insertion of the left ventricular (LV) lead and reduces the effectiveness of cardiac resynchronization therapy (CRT). A 77-year-old woman underwent dual-chamber pacemaker implantation via the left subclavian approach for a complete atrioventricular block 17 years previously. She was hospitalized due to decompensated heart failure, and her cardiac rhythm completely depended on ventricular pacing at that time. Transthoracic echocardiography showed thinning of the ventricular septum in the basal region and pacing-induced dyssynchrony. She was clinically diagnosed with cardiac sarcoidosis with severe LV systolic dysfunction. She was referred for an upgrade to CRT. Given that prior contrast venography showed occlusion of the left subclavian vein, an additional LV lead was inserted through the right subclavian vein. Coronary venography showed a lateral vein that branched from the great cardiac vein with an acute angle and had multiple tortuosities in the peripheral branches. Since the LV lead placement was unsuccessful with the conventional method, we attempted the lead placement using the balloon occlusion technique (BOT). Lead delivery into the anatomical optimal lateral vein was successful by using BOT, and LV pacing from the most delayed basal region was achieved in combination with the active fixation LV lead. .

Efficacy and safety of rivaroxaban in extreme elderly patients with atrial fibrillation: Analysis of the Shikoku Rivaroxaban Registry Trial (SRRT).

BACKGROUND: The Shikoku Rivaroxaban Registry Trial (SRRT) is a retrospective survey of the use of rivaroxaban for stroke prevention in elderly patients in Shikoku, Japan. METHODS: The SRRT enrolled 1339 patients from 8 hospitals. Patients were divided into two groups according to their age, the extreme elderly group (453 patients aged ≧80 years) and the control group (886 patients aged <80 years). RESULTS: In the extreme elderly group, 41.5% of the patients had low body weight (<50kg) and 65.1% had abnormal renal function (creatinine clearance <50ml/min). The mean CHADS2, CHA2DS2-VASc, and HAS BLED scores were 2.7, 4.4, and 2.3, respectively. There were 333 (73.5%) patients who met the dosing criteria, and of these patients, 81.2% received rivaroxaban 10mg daily. Thromboembolic events occurred in 4 patients (0.94%/person year) and intracranial hemorrhage occurred in 4 patients (0.89%/person year). The incidence of these events was not significantly different from the control group. In addition, all patients with cerebral infarction had been treated with a smaller dose of rivaroxaban than recommended by the dosing criteria, suggesting that dosing criteria should be adhered to. CONCLUSION: These results suggest that rivaroxaban is effective and safe in extreme elderly patients with atrial fibrillation.

Comprehensive arrhythmic surgery for sustained ventricular tachycardia revisited.

A 68-year-old woman with a history of old inferior myocardial infarction was admitted because of sustained ventricular tachycardia. Double vessel coronary disease was found with subtotal obstruction of the right coronary artery (#1) and severe stenosis of the left circumflex coronary artery (#13). Dilated left ventricle with a large ventricular aneurysm at the inferior wall and severely reduced systolic function were also present. A comprehensive surgical ablation using subendocardial resection and cryoablation was performed in combination with aneurysmectomy, left ventricular reconstruction, and coronary bypass grafting to the circumflex coronary artery. An implantable cardioverter-defibrillator was also implanted. She has remained well without recurrence of sustained ventricular tachycardia for one year. Although radiofrequency catheter ablation is nowadays considered a first-line therapy for patients with sustained ventricular tachycardia, surgical ablation remains a valuable option for selected patients, particularly for those requiring left ventricular aneurysmectomy and coronary artery bypass grafting, in order to gain a better long-term prognosis through total cure of ventricular tachycardia. .

Right ventricular mobile thrombus in end-stage hypertrophic cardiomyopathy.

We report the first case of a mobile right ventricular apical thrombus in hypertrophic cardiomyopathy in the absence of right ventricular apical aneurysm. An 87-year-old man who had been diagnosed as having hypertrophic cardiomyopathy presented with gross peripheral edema and exertional dyspnea. He had been on warfarin, ß-blockade, and diuretics. Electrocardiograms indicated progression of the disease with atrial fibrillation, low voltage and prominent Q waves in the left precordial leads. Echocardiograms revealed ventricular septal and apical hypertrophy, hypokinetic distal left ventricle, and dilated and severely hypokinetic right ventricle. A mobile thrombus (18 mm × 18 mm) was detected in the right ventricular apex. Cardiac computed tomography and magnetic resonance imaging confirmed a large thrombus in the right ventricular apex. Late gadolinium enhancement was present in the interventricular septum and distal segments of both ventricles, indicating myocardial fibrosis and scar. A dilated and poorly contracting right ventricle, particularly right ventricular apex, in end-stage hypertrophic cardiomyopathy, associated with stagnant blood flow in the apex, was hypothesized as being responsible for right ventricular apical thrombus formation in the absence of right ventricular aneurysm. .

Comparison of outcomes using the sirolimus-eluting stent in calcified versus non-calcified native coronary lesions in patients on- versus not on-chronic hemodialysis (from the j-Cypher registry).

The impact of lesion calcium on long-term outcomes after drug-eluting stent implantation has not been adequately addressed. In 10,595 patients (16,803 lesions) who were exclusively treated with sirolimus-eluting stents in the j-Cypher registry, 5-year outcomes were compared between patients with ≥1 lesion with moderate or severe calcification (the calcium group) and those with noncalcified lesions only (the noncalcium group). Analyses were stratified by hemodialysis (HD) status (non-HD stratum [calcium n = 3,191, noncalcium n = 6,824] and HD stratum [calcium n = 415, noncalcium n = 165]). Adjusted risk in the calcium group for death and target lesion revascularization was significant in the non-HD stratum (hazard ratio [HR] 1.34, 95% confidence interval [CI] 1.18 to 1.52, p <0.0001, and HR 1.2, 95% CI 1.07 to 1.36, p = 0.003) and the HD stratum (HR 1.4, 95% CI 1.06 to 1.86, p = 0.02, and HR 2.25, 95% CI 1.51 to 3.36, p <0.0001). Risk for definite stent thrombosis tended to be higher in the calcium group in the HD stratum (HR 5.05, 95% CI 0.66 to 38.9, p = 0.12) but not in then non-HD stratum (HR 1.16, 95% CI 0.81 to 1.67, p = 0.41). The use of rotational atherectomy in patients with severe calcification did not have a significant impact on the cumulative incidence of target lesion revascularization in the non-HD stratum (17.7% [n = 268] with vs 18.2% [n = 588] without rotational atherectomy, p = 0.68) and the HD stratum (54.7% [n = 115] with vs 51.9% [n = 118] without rotational atherectomy, p = 0.19). In conclusion, regardless of HD status, patients with calcified lesions have increased long-term risk for death and target lesion revascularization after sirolimus-eluting stent implantation.