Mehra, Nandini

AbstractIntroductionThe ablation of outflow tract premature ventricular contractions (PVCs) is generally safe and effective. In some patients, successful ablation sites may not correlate with the earliest activation. We sought to evaluate mechanistic and anatomic relevance of the region below the left sinus of Valsalva in variable morphology outflow tract ventricular arrhythmias.MethodsPVC cases where ablation was in the region inferior to the left sinus of Valsalva were identified. Procedural and demographic information and long‐term outcomes were obtained. Cadaver dissections to evaluate regional anatomy were done as well.ResultsA total of 51 cases were included (age 53 ± 10; 37 [73%] males). Ablation was done for high PVC burden (>20%; mean 27% ± 8%) and presence of symptoms (73%) or ejection fraction less than 50% (78%). QRS morphology included either R wave (8; 16%), Rs (9; 18%), or rS (67%) in lead I, no precordial transition (40; 78%), V2 transition, (7; 14%), or V3 transition (4; 8%). In 31 (61%), the site just below the left coronary cusp was the earliest site, while the remainder had another site earlier. Ablation was acutely successful in 50 of 51 (98%). After 3 months, success was noted in 48 of 51 (94%). In two patients, repeat ablation in the same region resulted in durable suppression.ConclusionThe cases presented emphasize the importance of a region centered below the left sinus of Valsalva, where multivariable morphology QRS may be successfully ablated. Consideration of mapping and ablation even when signals are late in this region may be warranted in previously failed ablation attempts or first‐line evaluation.

Abstract Background Outflow tract premature ventricular complexes (PVCs) may be ablated at sites where the local electrogram is early. We describe ablation of PVCs of varying morphology at a cruciate structure extending from the inflection of the great cardiac vein to the junction of the distal RVOT and from the left ventricular (LV) inflow myocardium through the aortic mitral continuity (AMC) to the right coronary sinus of Valsalva centered below LSOV, termed the LV crux. Purpose Evaluate a novel target for ablation of PVCs with varied QRS morphologies. Methods A series of 51 patients undergoing ablation for PVCs between 2013–2018 was identified. In all cases, ICE-guided ablation occurred at the center of the LV crux. Results All patients had high PVC burden >20% (28±8%); EF<50% in 40/51 (78%). QRS morphology of PVCs is summarized in Table 1. 50% had prior ablation attempted at early sites. Mapping and ICE-guided ablation at the LV crux (Figure 1 A-B) revealed early activation with near-field ventricular or fascicular signal in 31 (61%), while others had early sites at extensions of the crux. PVCs were eliminated in 50/51 (98%) with continued suppression at 3-months. EF normalized in all 51. Table 1. ECG charactaeristics ECG characteristics Number of patients (%) Inferior morphology 51/51 (100%) Lead I morphology Monophasic R 8/51 (16%) Rs 9/51 (18%) rS 34/51 (66%) Precordial transition Positive across precordium 40 (78%) V2 transition 7 (14%) V3 transition 4 (8%) Maximum deflection index <0.55 37 (73%) >0.55 14 (27%) Figure 1. Mapping and ablation Conclusions A cruciate interventricular multidimensional crux centered below the LSOV is a site for successful ablation of varied PVC morphologies and should be considered for detailed mapping and ablation, particularly when multiple morphologies are present or prior ablation at early sites is unsuccessful. Ventricular myocardial architecture along with conduction system remnants may be the basis for this phenomenon.

Background Premature coronary artery disease ( CAD ) is common in patients with coarctation of aorta ( COA ), but there are limited data about any direct relationship (or lack thereof) between COA and CAD . We hypothesized that atherosclerotic cardiovascular disease risk factors, rather than COA diagnosis, was the primary determinant of CAD occurrence in patients with COA . Methods and Results This is a retrospective study of 654 COA patients and a control group of 876 patients with valvular pulmonic stenosis and tetralogy of Fallot to determine prevalence and independent risk factors for CAD . There was no evidence of a difference in the unadjusted CAD prevalence between the COA and control groups (7.8% versus 6.3%, P =0.247), but premature CAD was more common in COA patients (4.4% versus 1.8%, P =0.002). In the analysis of a propensity‐matched cohort of 126 COA and 126 control patients, there was no evidence of a difference in overall CAD prevalence (6.3% versus 5.6% versus P =0.742) and premature CAD prevalence (4.8% versus 3.2%, P =0.518). The multivariable risk factors for CAD were hypertension (odds ratio [ OR ] 2.14; 95% CI 1.36–3.38), hyperlipidemia ( OR 3.33; 95% CI 2.02–5.47), diabetes mellitus ( OR 1.98; 95% CI 1.31–3.61), male sex ( OR 2.05; 95% CI 1.33–3.17), and older age per year ( OR 1.06; 95% CI 1.04–1.07). Conclusions After adjusting for atherosclerotic cardiovascular disease risk factors, we did not find evidence of a difference in CAD risk between the patients with COA and other patients with congenital heart disease.

Background Patients with tetralogy of Fallot ( TOF ) remain at risk for cardiovascular events despite successful repair. Some of the current risk stratification tools require advanced imaging and invasive studies, and hence are difficult to apply to routine patient care. A recent study showed that QRS fragmentation ( QRS ‐f) is predictive of mortality in patients with TOF. The current study aims to validate this result by assessing whether severity of QRS ‐f could predict all‐cause mortality in a different TOF population. Methods and Results The authors reviewed the Mayo Adult Congenital Heart Disease database for patients with TOF who had ECG from 1990–2017. QRS ‐f was defined as notches in QRS complex in ≥2 contiguous leads on ECG , not related to bundle branch block, and classified as none, mild (≤3 leads), moderate (4 leads), or severe (≥5 leads). Of 465 patients (age 37±14 years) in the study, QRS ‐f was present in 161 (35%): mild (n=43, 9%), moderate (n=77, 17%), and severe (n=41, 9%). There were 55 deaths (12%) during 13.6±8.2 years of follow‐up. Severity of QRS ‐f remained an independent predictor of all‐cause mortality after adjustment for other ECG parameters, patient demographics, and atrial and ventricular arrhythmia (hazard ratio, 1.74 per class; 95% confidence interval, 1.08–2.93 [ P =0.041]). Conclusions The presence of severe QRS ‐f may be used as complementary data to the usual clinical indices to determine whether interventions such as invasive electrophysiology study should be performed in patients with nonsustained ventricular tachycardia or to proceed with pulmonary valve replacement in patients with severe pulmonary regurgitation with ventricular volumes below the guideline‐directed threshold for intervention.