Optimizing Patient Selection for Physiological Pacing in Bradyarrhythmia: Factors Associated With High Ventricular Pacing Burden.

Background: Right ventricular (RV) pacing is established as the most common ventricular pacing (VP) strategy for patients with symptomatic bradyarrhythmia. Some patients with high VP burden suffer deterioration of left ventricular (LV) function, termed pacing-induced cardiomyopathy (PICM). Patients who pace > 20% of the time from the RV apex are at increased risk of PICM, but independent predictors of increased RV pacing burden have not been elucidated in those who have a permanent pacemaker (PPM) inserted for bradyarrhythmia. Methods: We aimed to identify factors that are associated with increased VP burden > 20%, hence determining those at risk for resultant PICM. In this retrospective cohort study, we identified the most recent 300 consecutive cardiac implantable electronic device (CIED) implants in our center and collected past medical history, electrocardiogram (ECG), echo, medication and pacemaker check data. Results: A total of 236 individuals met inclusion criteria. Of the patients, 35% had RV pacing burden < 20%, while 65% had VP burden ≥ 20%; 96.2% of patients with complete heart block (CHB) paced > 20% (P = 0.002). Utilization of DDD or VVI (75.2% and 89.2% of patients, respectively) without mode switch algorithms was associated with VP > 20% (P < 0.001). Male or previous coronary artery bypass grafting (CABG) patients also statistically paced > 20%. Other factors trending towards significance included prolonged PR interval, atrial fibrillation or more advanced age. Conclusion: High-grade atrioventricular (AV) block was associated with an RV pacing burden > 20% over 3 years but this was not consistent in patients with only transient episodes of high-grade AV block. We found a significant association between high VP% and male sex, previous CABG and the absence of mode switching algorithms.

Evaluation of Effectiveness and Tolerability of Fondaparinux in the Management of Symptomatic Acute Coronary Syndrome: A Real-World Evidence-Based Study on an Indian Population.

INTRODUCTION: Fondaparinux is a low molecular weight heparin anticoagulant used to manage the full spectrum of acute coronary syndrome (ACS) patients and has proved its efficacy and safety in multiple clinical trials. However, there are limited data available showing whether the same results could be reproduced in real-world practice on an Indian population. Our objective was to determine the effectiveness and tolerability of fondaparinux in the management of symptomatic ACS in real-world clinical practice. METHODS: The EMR data of hospitalized ACS patients (n = 611), from January 2015 to January 2020, representing UA or NSTEMI or STEMI and were prescribed fondaparinux (2.5 mg once daily) to manage ACS were analyzed. The effectiveness was analyzed as recurrence of ACS and tolerability as total incidence of major bleeding during hospitalization, at 30 days and 180 days. Appropriate statistical analysis was used with a statistically significance of p value < 0.05. RESULTS: The incidence of recurrent ACS was not seen during hospitalization and in the first 30 days, while in only 0.65% (n = 4) patients, ACS reoccurred within 180 days. In a mean duration of 172.75 ± 3.20 days, UA was reported in 0.49% (n = 3) patients, NSTEMI in 0.16% (n = 1) of patients, and STEMI was not documented. None of the major bleeding events occurred during the entire study period, whereas minor bleeding events were reported during hospitalization 0.98% (n = 6) and at 30 days 0.16% (n = 1). The bleeding events were statistically insignificant (p value > 0.05). No incidences of stent thrombosis were reported during the entire study period. CONCLUSIONS: In the real world, fondaparinux was found to be effective and tolerable when used to manage symptomatic ACS patients regardless of revascularization procedure with no incidence of stent thrombosis, and minimal recurrent ACS and insignificant increase in bleeding events.

Effectiveness and Tolerability of Fondaparinux vs Enoxaparin in a Population of Indian Patients with Symptomatic Deep Vein Thrombosis: A Retrospective Real-World Study.

BACKGROUND: Fondaparinux is the first approved anticoagulant drug among factor Xa inhibitors, with proven effectiveness and safety in preventing deep vein thrombosis. However, limited data are available supporting the benefit-risk profile of fondaparinux vs enoxaparin in a real-world group of Indian patients with deep vein thrombosis. OBJECTIVE: To compare the effectiveness and tolerability of fondaparinux vs enoxaparin in patients with symptomatic deep vein thrombosis in a long-term real-world setting. METHODS: Data from the electronic medical records of adult patients diagnosed with deep vein thrombosis prescribed fondaparinux (n = 503) or enoxaparin (n = 508) as monotherapy were analyzed. Effectiveness was analyzed in terms of recurrence, duration, and type of deep vein thrombosis event, and tolerability as bleeding events at initial hospitalization and follow-up visits up to 3 months duration. Appropriate statistical methods were used to determine the significance (p < 0.05) between the two groups. RESULTS: The deep vein thrombosis recurrence in the fondaparinux group was non-inferior (2.78%) when compared with enoxaparin (3.76%), with a mean duration of 47 and 48 days, respectively. The number of events and mean duration of events (in days) were not significant (p > 0.05). Major bleeding events were higher in the enoxaparin group at 3.17% than the fondaparinux group at 2.19%, and the difference was not statistically significant (p > 0.05). CONCLUSIONS: The weight-based, once-daily subcutaneous fondaparinux dose showed non-inferior effectiveness and a comparable tolerability profile when compared with the twice-daily enoxaparin dose for the management of symptomatic deep vein thrombosis.

Isolated left ventricular non-compaction in association with ventricular tachycardia.

A 32-year-old young male was found to have non-sustained, repetitive, monomorphic ventricular tachycardia of right bundle branch morphology during routine pre-anaesthetic evaluation for orthopaedic surgery. Echocardiography and left ventricular angiogram were suggestive of isolated non-compaction of left ventricular apex with systolic dysfunction. He was successfully managed with anti-arrhythmic drugs and had an uneventful 9-month follow-up. The index case is an unusual association of asymptomatic, non-sustained ventricular tachycardia with isolated ventricular non-compaction.

Effect of percutaneous transvenous mitral commissurotomy on left atrial appendage function: an immediate and 6-month follow-up transesophageal Doppler study.

BACKGROUND: The left atrial appendage (LAA) is a common site of thrombus formation and is the source of systemic thromboembolism in patients with rheumatic mitral stenosis. LAA contractile dysfunction is a common finding in these patients. The aim of this study was to assess immediate and 6-month follow-up LAA function by transesophageal Doppler echocardiography in patients who underwent percutaneous transvenous mitral commissurotomy (PTMC). METHODS: Forty-seven consecutive patients with symptomatic critical mitral stenosis who underwent PTMC were enrolled. All had underwent transthoracic and transesophageal echocardiography before, 24 hours after, and 6 months after PTMC. Pulse Doppler velocities of the LAA were measured, including peak early diastolic (E wave), peak late diastolic (A wave), and peak systolic (S wave). The corresponding tissue Doppler velocities of the LAA, including peak early diastolic (E(LAA)), peak late diastolic (A(LAA)), and peak systolic (S(LAA)), were also measured. LAA ejection fraction was measured using the modified Simpson's method. RESULTS: The mean age of the 47 enrolled patients was 31.7 ± 10.26 years. Thirty-eight patients were in sinus rhythm, and the remaining nine were in atrial fibrillation. PTMC was successful in all patients. The pulse Doppler velocities of the LAA at baseline, after PTMC, and at 6-month follow-up were as follows: for the E wave, 15.29 ± 2.26, 17.02 ± 2.25, and 17.97 ± 2.55 cm/sec, respectively (P < .001); for the A wave 22.45 ± 4.11, 24.19 ± 4.21, and 25.99 ± 4.51 cm/sec, respectively (P < .001); and for the S wave, 28.52 ± 4.37, 31.45 ± 5.37, and 33.06 ± 4.99 cm/sec, respectively (P < .001). The corresponding tissue Doppler velocities of LAA were as follows: for E(LAA), 4.65 ± 0.91, 5.28 ± 0.85, and 5.80 ± 0.84 cm/sec, respectively (P < .001); for A(LAA), 6.67 ± 1.12, 7.33 ± 1.17, and 7.88 ± 1.22 cm/sec, respectively (P < .001); and for S(LAA), 4.67 ± 1.12, 5.52 ± 1.18, 6.07 ± 1.11 cm/sec, respectively (P < .001). There was a nonsignificant increase in LAA ejection fraction (48.97 ± 8.14% vs 52.3 ± 13.76% vs 52.11 ± 16.3%, respectively, P = .052). On subgroup analysis between patients in sinus rhythm and those with atrial fibrillation, there was no significant difference for LAA ejection fraction and pulse and tissue Doppler velocities. Very good intraclass correlation of the LAA parameters was also observed for the reproducibility of the data. CONCLUSIONS: The present study shows contractile dysfunction of the LAA in patients with critical mitral stenosis, which significantly improved after PTMC, and a further improvement was observed at 6-month follow-up. Favorable 6-month improvements in LAA parameters suggest continuous structural remodeling of the LAA after PTMC, which is clinically attributed to the absence of thromboembolism. Although there was an improvement in LAA function, it was far below the normal range, suggesting a need for continuous long-term monitoring and management of thromboembolism in these patients.