In search for "healthy" landing zones for coronary stent placement: are the largest intrasegmental lumens adequate?

Background: Coronary lesions are supposed to be enclosed between proximal and distal reference segments (RSs), the sites with the largest lumens within the same vessel segment. Finding "healthy" landing zones has been fundamental for efficient stent implantation. Consequently, our study aimed to determine, using optical coherence tomography (OCT), to what degree RSs conform to this concept. Methods: Sixty-seven patients with a mean age of 63.5 years underwent culprit lesion stenting due to acute myocardial infarction (MI) (Group 1) or stable angina (Group 2). OCT was performed with commercially available equipment; all evaluations were made at RSs and minimal lumens. Results: Normal vessel wall was infrequent (~10%) at RSs. Acceptable external elastic 220°) occurred in 55% to 67% and in 28% to 31% of RSs, respectively. Tissue composition at RSs was similar in both study groups except for a greater accumulation of thin-cap fibroatheromas (TCFA) in acute MI (29% in Group 1 vs. 9% in Group 2, P=0.035). Flow deterioration after stenting was associated with TCFA clusters extending from culprit main bodies into proximal RSs (P=0.008). Conclusions: Optimal landing zones for stent placement should frequently be searched for beyond the culprit lesion segments although utilizing the largest intrasegmental lumens does not seem to cause immediate harm. However, TCFA at the landings should definitely be avoided.

Biventricular versus His bundle pacing after atrioventricular node ablation in heart failure patients with narrow QRS.

Background: His bundle pacing (HBP) is a physiological alternative to biventricular (BiV) pacing. We compared short-term results of both pacing approaches in symptomatic atrial fibrillation (AF) patients with moderately reduced left ventricular (LV) ejection fraction (EF ≥35% and <50%) and narrow QRS (≤120 ms) who underwent atrioventricular node ablation (AVNA).Methods: Thirty consecutive AF patients who received BiV pacing or HBP in conjunction with AVNA between May 2015 and January 2020 were retrospectively assessed. Electrocardiographic, echocardiographic, and clinical data at baseline and 6 months after the procedure were assessed.Results: Twenty-four patients (age 68.8 ± 6.5 years, 50% female, EF 39.6 ± 4%, QRS 95 ± 10 ms) met the inclusion criteria, 12 received BiV pacing and 12 HBP. Both groups had similar acute procedure-related success and complication rates. HBP was superior to BiV pacing in terms of post-implant QRS duration, implantation fluoroscopy times, reduction of indexed LV volumes (EDVi 63.8 (49.6-81) mL/m2 vs. 79.9 (66-100) mL/m2, p = 0.055; ESVi 32.7 (25.6-42.6) mL/m2 vs. 46.4 (42.9-68.1) mL/m2, p = 0.009) and increase in LVEF (46 (41-55) % vs. 38 (35-42) %, p = 0.005). However, the improvement of the NYHA class was similar in both groups.Conclusions: In symptomatic AF patients with moderately reduced EF and narrow QRS undergoing AVNA, HBP could be a conceivable alternative to BiV pacing. Further prospective studies are warranted to address the outcomes between both 'ablate and pace' strategies.

Impact of left ventricular pacing threshold on ventricular arrhythmia occurrence in cardiac resynchronization therapy.

BACKGROUND: Cardiac resynchronization therapy (CRT) is an established heart failure (HF) treatment option, however its effect on ventricular arrhythmias (VAs) is controversial. Regional scar burden and high left ventricular (LV) pacing threshold (PT) are associated with poor outcome in CRT patients. The aim of our study was to analyze the impact of intraoperative LVPT on VA occurrence. METHODS: Eighty consecutive patients with advanced HF scheduled for a CRT defibrillator device [aged 63.3±10.9 years; New York Heart Association II-III 86.2%; 52 males (65%); 34 ischemic etiology (42.5%); 71 sinus rhythm (88.7%); QRS duration 168±25.7ms] were evaluated using single-photon emission computed tomography myocardial perfusion imaging. Regional myocardial viability was calculated as the mean tracer activity in the corresponding segments at the LV lead pacing site. Fluoroscopic position and intraoperative LVPT were determined at implant after the final LV lead position was determined. RESULTS: LVPT was inversely associated with regional myocardial viability (ρ -0.785, p<0.001). After a median follow-up of 36 months (24-57) months VAs were registered in 27 patients (33.7%). Patients with VAs had higher median intraoperative LVPT compared to those without VAs [2.2V (1.9-2.8) vs. 0.8V (0.6-1.2), p<0.001]. In a multivariate logistic regression model intraoperative LVPT was identified as a strong independent predictor of VAs. CONCLUSION: Increased intraoperative LVPT during CRT could be associated with lower regional myocardial viability at LV lead location. CRT patients with higher LVPT could have an increased risk of VA occurrence.

Robustness of Percutaneously Completed Coronary Revascularization in Stable Coronary Artery Disease: Obstructive Versus Occlusive Lesions.

Our study sought to assess long-term outcomes of percutaneously completed coronary revascularization (CCR) in patients with obstructive coronary artery disease (CAD) comprising chronic total occlusions (CTOs). Between 2010 and 2014, percutaneous coronary interventions (PCIs) of the CTOs were attempted in 213 patients: the CCR was achieved in 125 patients (group 1), while the PCI failed in 88 patients (group 2). They were matched against 252 patients (group 3) with the CCR obtained by the non-CTO PCIs. In the 5-year follow-up, more adverse cardiovascular (CV) events occurred in group 2 (29.5% vs 4.8% in group 1 vs 3.5% in group 3, P = .0001), mainly due to recurrent severe symptoms and additional revascularization of the CTOs; CV mortality did not seem to be significantly affected. Survival curves for the successful CTO and non-CTO PCIs appeared indistinguishable. Stent thromboses were infrequent in the CCR groups. In conclusion, long-term outcomes of the patients with the obstructive CAD containing the CTOs showed a favorable outcome if the CCR had been achieved percutaneously.