QRS axis and polarity in the inferior leads during left bundle branch pacing: Novel criteria in the search for better results.

BACKGROUND: Left bundle branch pacing (LBBP) may be achieved in various anatomical sites within the interventricular septum (IVS), thus influencing paced QRS duration (QRSd).The purpose of this study was to determine whether paced QRS axis (QRSâ) and predominant polarity in inferior leads could be associated with a shorter paced QRSd. METHODS: We analyzed paced QRSd, QRSâ, polarity in inferior leads, and IVS thickness in patients referred for LBBP. Three paced morphology patterns in the inferior leads were considered: All positive (P), all negative (N) and intermediate (combination of isoelectric, positive, and negative complexes, (I). Patients were divided into two groups according to a paced QRSd < 120 or ≥ 120 ms. RESULTS: A total of 125 patients were included (age 76 ± 10 years, 46% female). Mean baseline QRSâ was 8 ± 37°. Paced QRSd was significantly shorter as compared to baseline (120 ± 10 vs. 127 ± 33 ms; p = .017) and significantly different according to paced QRS morphology pattern in the inferior leads (P 49%, 119 ± 9; N 30%, 126 ± 12; I 21%; 113 ± 10 ms; p < .001) or paced QRSâ (Normal 59%, 116 ± 1; Right 6%, 129 ± 1; Left 35%, 124 ± 11 ms; p < .001). On multivariate analysis, a QRSâ > -30°(OR 5.79 [2.40-13.93; 95% CI] p = .001), an Intermediate pattern in inferior leads (OR 3.00 [1.67-8.43; 95% CI] p = .037), and an IVS thickness ≤ 10 mm (OR 2.59 [1.10-6.10; 95% CI]; p = .029) were significantly associated with a paced QRSd < 120 ms. CONCLUSIONS: During LBBP, a QRSâ > -30° and intermediate final polarity in inferior leads are associated with a shorter paced QRSd.

Improvement in quality of life with sacubitril/ /valsartan in cardiac resynchronization non-responders: The RESINA (RESynchronization plus an Inhibitor of Neprilysin/Angiotensin) registry.

BACKGROUND: Clinical management of cardiac resynchronization therapy (CRT) non-responders is difficult, and their prognosis is poor. The aim of the present study was to evaluate whether treatment with sacubitril/valsartan can improve quality of life (QoL) parameters in these patients. METHODS: Thirty five non-responders to CRT were included (75 ± 7 years, 28% females, mean left ventricular ejection fraction 28 ± 8%, 54% non-ischemic cardiomyopathy) with maximally optimized drug therapy and New York Heart Association class II-III. They were all on angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers and were switched to sacubitril/valsartan. One week before and 6 months after initiation of the therapy they completed both the Minnesota Living with Heart Failure (MLWHF) and the 12-item Kansas City Cardiomyopathy Questionnaires (KCCQ-12). The primary outcome was the effect of sacubitril/valsartan on the physical, clinical, social and emotional QoL parameters and number of hospitalizations. RESULTS: The mean total scores of both questionnaires improved from baseline to the follow-up visit at 6-months (KCCQ-12 40 ± 10 to 47 ± 10; p < 0.001; MLWHF 40 ± 15 to 29 ± 15; p < 0.001). The best results were seen in the KCCQ-12 total symptom domains (77% improvement), the MLWHF physical domain (81% improvement), and the MLWHF emotional domain (71% improvement). Two patients died during follow-up. The mean number of hospitalizations reduced significantly (1 ± 0.6 vs. 0.5 ± 0.8; p = 0.003) CONCLUSIONS: In CRT non-responders, sacubitril/valsartan significantly improved overall QoL, physical limitations and emotional domains and reduced the number of hospitalizations.

A novel simple, fast, and safe approach for effective superior vena cava isolation using the third-generation cryoballoon.

BACKGROUND: Superior vena cava (SVC) isolation with radiofrequency energy remains a challenge due to potential side effects, especially phrenic nerve (PN) or sinus node injury. The purpose of this study was to evaluate the feasibility of a novel SVC isolation technique using the third-generation cryoballoon (CB3). METHODS: Patients undergoing atrial fibrillation (AF) ablation were prospectively included. The procedure was performed with the CB3, beginning with the pulmonary veins and ending with SVC isolation. During applications in the SVC, continuous PN capture and sinus rate were monitored. Once reached SVC isolation during the application, 60 s more was applied, with no bonus application. If after 90 s the SVC was not isolated, application was stopped. A maximum number of four applications were permitted. RESULTS: Thirty patients (62 ± 9 years; 74% male, 78% paroxysmal AF) were included. No SVC activity was observed in two patients. Success rate for SVC isolation was 89%. Mean number of applications per patient was 2.3 ± 1. Mean time to SVC isolation was 37 ± 20  s. Mean duration of application was 92 ± 15 s. Mean total time of procedure for SVC isolation was 218 ± 43 s. We recorded only two complications: one transient PN palsy and one short and transient sinus arrest. After a mean follow-up of 5 ± 2 months, 89% are free from arrhythmia recurrence. CONCLUSIONS: We present a promising simple SVC-isolation technique using CB3, featuring a high success rate and very low incidence of complications.

Detecting Atrial Fibrillation in Patients With an Embolic Stroke of Undetermined Source (from the DAF-ESUS registry).

Atrial fibrillation (AF) causes a substantial proportion of embolic strokes of undeterminded source (ESUS). Effective detection of subclinical AF (SCAF) has important therapeutic implications. We conducted a prospective study to determine the prevalence of SCAF in patients with ESUS through of a 21-day Holter monitoring. In an early-monitoring group, Holter was initiated immediately after hospital discharge. The results were compared with a previous cohort of patients in whom the Holter was initiated at least 1 week after hospital discharge (late-monitoring group). We included 100 patients (50 each group; 69 ± 13 years, 56% male). Mean time from ESUS to Holter was 1.2 ± 1 day in the early-monitoring group and 30 ± 15 days in the late-monitoring group. SCAF was detected in 22% of patients in the early-monitoring and 6% in the late-monitoring group (p <0.05). Patients with SCAF were older (77 ± 9 vs 67 ± 11 years, p <0.05), with a higher rate of left atrial enlargement (50% vs 20%, p<0.05), renal impairment (28% vs 5%; p<0.01), and a slower mean heart rate (55 ± 6 vs 70 ± 6 beats/min; p<0.001). On multivariate analysis, the presence of persistent bradycardia (≤60 beats/min) in the 21-day Holter was a powerful and significant risk factor for SCAF. In conclusion, the sooner 21-day Holter electrocardiogram monitoring is initiated after ESUS, the more likely SCAF can be detected. Sinus bradycardia is a powerful predictor of SCAF in patients with ESUS.