left bundle branch block

A 73-year-old male underwent cardiologic evaluation for an incidental electrocardiographic finding of left bundle branch block (LBBB). He was asymptomatic and had no relevant cardiac history. Physical examination and transthoracic echocardiogram revealed no abnormalities.

Biventricular (BiV) pacing revolutionized the heart failure management in patients with sinus rhythm and left bundle branch block; however, left ventricular-lead placement is not always technically possible. Also, BiV pacing does not fully normalize ventricular activation and, therefore, the ventricular resynchronization is imperfect. On the other hand, right ventricular pacing for bradycardia may cause or worsen heart failure in some patients by causing dyssynchronous ventricular activation. His bundle pacing comes as an alternative to current approaches as it activates the ventricles via the native His-Purkinje system, resulting in true physiological pacing, and, therefore, is a promising site for pacing in bradycardia and traditional CRT indications in cases where it can overcome left bundle branch block. Furthermore, it has the potential to open up new indications for pacing therapy in heart failure, such as targeting patients with PR prolongation, but a narrow QRS duration. In this article we explore the history, clinical evidence, proposed mechanisms, procedural characteristics, and the role in current therapy of His bundle pacing in the prevention and treatment of heart failure.

Background and aim of the study: Sutureless aortic valves are used to reduce operation time. However, the stent implantation might cause postoperative ECG alterations and a higher risk of paravalvular leakage. In literature, some cases of thrombocytopenia are described after implantation. We investigated the Sorin Perceval S Sutureless Valve and the Edwards Intuity Sutureless Valve.Material and methods: Seventy-nine patients underwent aortic valve replacement using a sutureless valve in a single center between 2015 - 2018. Thirty-seven patients received Sorin Perceval S (Group A) and 42 Edwards Intuity (Group B). Simultaneous bypass surgery was performed in 23 patients in Group A and 22 patients in Group B. We compared the groups regarding postoperative TTE and paravalvular leakage, postoperative ECG alterations, need for pacemaker implantation, postoperative platelet count, and 30-day mortalityResults: Only in Group B 2 patients had paravalvular leakage, and one was reoperated within the same hospital stay. In Group A, nine patients suffered from postoperative atrial fibrillation, and in Group B, 16 patients. Left bundle branch block (LBBB) was observed in 5 patients in Group A, and 13 patients in Group B. Two patients in Group A needed a definite pacemaker, and five patients in Group B. Tachy-Brady Syndrome and LBBB were observed more frequently in Group B as well as ECG alterations. One patient died within 30 days in Group A due to multiorgan failure. This patient was older and multimorbid compared to the average. Regarding platelet count, we saw a statistically significant decrease in both groups. There were no major bleeding complications or reoperations due to hemorrhage.Conclusion: Our data shows that sutureless aortic valve replacement is associated with new postoperative ECG alterations, which are self-limiting in most cases. Compared to the literature pacemaker implantation rate in Group B is higher.