Journal and News Scan

Segmentectomy is on the rise, but understanding of the segmental bronchial branching pattern is limited. Computed tomography scans of 303 patients were used to determine and categorize the branching of the right upper lobe bronchi. Four major types and eleven subtypes were identified. Volumetry was done to determine the predominant segment in each case. The order of frequency of branching types was trifurcated nondefective (64.4 percent), then bifurcated nondefective (22.1 percent), bifurcated defective (8.6 percent), and trifurcated half-defective (4.0 percent). In 71 percent of cases, one segment was volumetrically predominant, and in 52 percent of all cases this was segment three. There was a higher risk of complex branching in the volumetrically nonpredominant segment and care should be taken during segmentectomy of these segments.

Surgical tricuspid valve replacement (TVR) is associated with a high risk of postoperative atrioventricular (AV) block. However, placing pacemaker leads through a tricuspid bioprosthesis is discouraged since it might impair bioprosthesis function. Hence, alternative pacing approaches should be considered according to current cardiac pacing guidelines. 

This single center retrospective study assessed the benefits and risks of prophylactic epicardial pacemaker implantation during TVR. A total of eighty patients, with a mean age of fifty-seven years, who underwent TVR with concomitant prophylactic epicardial pacemaker implantation were analyzed. TVR was isolated in 28, or 35 percent of patients, but patients with other concomitant procedures were also included. During the postoperative period, with a mean follow-up period of thirty-five months, heart rhythm was analyzed in fifty-nine out of eighty patients. Cardiac pacing was needed in twenty-seven out of fifty-nine, or 46 percent of patients. Eight, or 14 percent, of patients had complete pacing dependency; ten, or 17 percent, of patients had a high degree AV block; nine, or 15 percent, of patients had a high ventricular pacing rate of over 80 percent. A postoperative spontaneous heart rate of over 70 bpm (P = 0.02) and the presence of a narrow QRS-complex (P = 0.03) were identified as predictors of lower cardiac pacing requirement. Epicardial pacemaker implantation was safe, with related complications observed in two, or 2.5 percent of patients. 

Given the frequent occurrence of AV block following TVR and the acceptable safety profile, the authors concluded that the prophylactic epicardial pacing strategy in patients undergoing TVR should be considered. The results from this study provide additional information to discuss the need for prophylactic epicardial pacing in patients undergoing tricuspid valve surgery.

This study determined which measurement—height, weight, BMI, BSA, predicted heart mass, total cardiac volume (TCV)—is most important for assessing donor-recipient heart size mismatch. Amdani and colleagues investigated the Pediatric Heart Transplant Society Database to address this question and identify the effects of donor-recipient size mismatch using a range of parameters. Outcomes were assessed at one and five years of follow up. Interestingly, they report that height and TCV are more relevant to long-term risk of graft loss compared to other metrics. 

The outcomes of the Transcatheter Aortic Valve Replacement in Low-Risk Patients at Five Years (5y PARTNER 3 trial) were presented during the late-breaking clinical trial session of TCT 2023 and simultaneously published in the New England Journal of Medicine. The results give valuable insights and add new evidence for the decision making and treatment of low-risk patients with severe symptomatic AS.

The PARTNER 3 trial randomly assigned 1,000 patients with severe symptomatic aortic stenosis (AS) and low surgical risk (STS-PROM < 4 percent) to undergo either transcatheter aortic valve replacement with a balloon expandable bioprosthesis (503 patients) or surgical aortic valve replacement (497 patients) with a prespecified superiority hypothesis. The two primary endpoints were composite of death, stroke, or rehospitalization, and hierarchical composite of death, disabling stroke, nondisabling stroke, and the number of rehospitalization days.

At five years, there was no significant difference in the risk of death, stroke, or rehospitalizations between the transcatheter aortic valve replacement (TAVR) and surgical aortic valve replacement (SAVR) arms. The Kaplan–Meier estimates were 22.8 percent vs. 27.2 percent in the TAVR and SAVR groups, respectively; p=0.07. Furthermore, Kaplan-Meier curves did not show a statistical difference in the five-year all-cause mortality. At five years, there was a mortality of 10.0 percent vs. 8.2 percent in the TAVR and SAVR groups, respectively; HR 1.23 and 95 percent CI 0.79-1.90. Remarkably, the Kaplan-Meier all-cause mortality curves initially showed an early result favoring TAVR, but beyond one year, attenuation of the observed differences occurred, with the curves crossing close to 36 months. The risk of cardiovascular (HR 1.08; 95 percent CI 0.61–1.92) and noncardiovascular (HR 1.46; 95 percent CI 0.74–2.90) mortality was similar in both groups. Valve hemodynamics were similar in both study arms, with a mean valve gradient 12.8±6.5 mmHg vs. 11.7±5.6 mmHg in the TAVR and SAVR groups, respectively. 

Moreover, bioprosthetic valve failure defined by VARC-3 criteria occurred at similarly low rates in both groups: 3.3 percent vs. 3.8 percent in the TAVR and SAVR groups, respectively. However, TAVR was associated with an increased risk of valve thrombosis: 0.2 percent vs. 2.5 percent; HR 10.52 (95 percent CI 1.37–80.93). Patient-reported health status was similar in the two groups, with a mean Kansas City Cardiomyopathy Questionnaire–Overall Summary score (KCCQ-OS) of 86.2 vs. 85.9 in the TAVR and SAVR groups, respectively. Similarly, 84.4 percent vs. 86.0 percent of the patients in the TAVR and SAVR groups presented with a New York Heart Association (NYHA) class I or II at five years, respectively.