Prognostic and Safety Implications of Renin-Angiotensin-Aldosterone System Inhibitors in Hypertrophic Cardiomyopathy: A Real-World Observation Over 2,000 Patients

Background and Objectives@#The prognostic or safety implication of renin-angiotensinaldosterone system inhibitors (RASi) in hypertrophic cardiomyopathy (HCM) are not well established, mainly due to concerns regarding left ventricular outflow tract (LVOT) obstruction aggravation. We investigated the implications of RASi in a sizable number of HCM patients. @*Methods@#We enrolled 2,104 consecutive patients diagnosed with HCM in 2 tertiary university hospitals and followed up for five years. RASi use was defined as the administration of RASi after diagnostic confirmation of HCM. The primary and secondary outcomes were all-cause mortality and hospitalization for heart failure (HHF). @*Results@#RASi were prescribed to 762 patients (36.2%). During a median follow-up of 48.1months, 112 patients (5.3%) died, and 94 patients (4.5%) experienced HHF. Patients using RASi had less favorable baseline characteristics than those not using RASi, such as older age, more frequent history of comorbidities, and lower ejection fraction. Nonetheless, there was no difference in clinical outcomes between patients with and without RASi use (log-rank p=0.368 for all-cause mortality and log-rank p=0.443 for HHF). In multivariable analysis, patients taking RASi showed a comparable risk of all-cause mortality (hazard ratio [HR], 0.70, 95% confidence interval [CI], 0.43–1.14, p=0.150) and HHF (HR, 1.03, 95% CI, 0.63–1.70, p=0.900). In the subgroup analysis, there was no significant interaction of RASi use between subgroups stratified by LVOT obstruction, left ventricular (LV) ejection fraction, or maximal LV wall thickness. @*Conclusions@#RASi use was not associated with worse clinical outcomes. It might be safely administered in patients with HCM if clinically indicated.

Predictive Value of Electromechanical Window for Risk of Fatal Ventricular Arrhythmia

Background@#As an indicator of electro-mechanical coupling, electromechanical window (EMW) can be used to predict fatal ventricular arrhythmias. We investigated the additive effect of EMW on the prediction of fatal ventricular arrhythmias in high-risk patients. @*Methods@#We included patients who had implantable cardioverter-defibrillator (ICD) implanted for primary or secondary prevention. The event group was defined as those who received an appropriate ICD therapy. We acquired echocardiograms at ICD implantation and follow-up. The EMW was calculated as the difference between the interval from QRS onset to aortic valve closure and QT interval from the electrocardiogram embedded in the continuous wave doppler image. We evaluated the predictive value of EMW for predicting fatal ventricular arrhythmia. @*Results@#Of 245 patients (67.2 ± 12.8 years, 63.7% men), the event group was 20.0%. EMW at baseline (EMW-Baseline) and follow-up (EMW-FU) was significantly different between event and control groups. After adjustment, both EMW-Baseline (odds ratio [OR]adjust 1.02 [1.01– 1.03], P = 0.004) and EMW-FU (ORadjust 1.06 [1.04–1.07], P < 0.001) remained as significant predictors for fatal arrhythmic events. Adding EMW-Baseline significantly improved the discriminating ability of the multivariable model including clinical variables (area under the curve [AUC] 0.77 [0.70–0.84] vs. AUC 0.72 [0.64–0.80], P = 0.004), while a univariable model using EMW-FU alone showed the best performance among models (AUC 0.87 [0.81– 0.94], P = 0.060 against model with clinical variables; P = 0.030 against model with clinical variables and EMW-Baseline). @*Conclusion@#The EMW could effectively predict severe ventricular arrhythmia in ICD implanted patients. This finding supports the importance of incorporating the electro-mechanical coupling index into the clinical practice for predicting future fatal arrhythmia events.

Duo‑decapolar catheter entrapment in the Chiari network: successful extraction with the snare catheter

Background@#The Chiari network (CN) is the net-like embryonic remnants of the right valve of the sinus venosus.Catheter entrapment by CN is a not uncommon complication during catheter manipulation inside the right atrium (RA).Case presentation A 49-year-old man with atrial fibrillation was admitted for cryoablation. Transesophageal echo‑ cardiography revealed a prominent CN in the RA. Through the sheath placed in the right femoral vein, a diagnostic electrophysiologic duo-decapolar (DD) catheter (Livewire, St Jude Medical, St Paul, MN) was advanced. The catheter tip was knotted after multiple rotations in the RA to properly locate the DD catheter at the RA wall and coronary sinus (CS). Initial attempts to disentangle the folded catheter tip by traction and rotation maneuvers were unsuccessful.We inserted the large-bore sheath (Sentrant; Medtronic, 20 Fr) into the patient’s left femoral vein and then, captured the folded catheter tip with the 20-mm circular snare catheter (Snare Kit, Medtronic, Minneapolis, MN). Then, we cut the proximal portion of the DD catheter externally and removed it retrogradely through the Flexcath sheath. We found that the catheter tip was entrapped by the fibrous tissue of the CN. After a successful retrieval, cryoablation was conducted as planned. Follow-up echocardiography did not reveal any peri-procedural complications. @*Conclusions@#The electrophysiological procedure that exists at the RA entails a potential risk of catheter entrapment manipulating the catheter at the RA. If catheter entrapment occurs during the procedure, the entrapped catheter may be removed via a large-bore sheath using a snare catheter.

Revascularization Strategies in Patients With ST-Segment Elevation Myocardial Infarction and Multivessel Disease: Is FFR-Guided Strategy Still Valuable?

Several studies have shown the benefit of complete revascularization (CR) over culprit-only percutaneous coronary intervention (PCI) in patients with ST-segment elevated myocardial infarction (STEMI) and multivessel disease (MVD). Nevertheless, optimal strategy to select targets for non-culprit PCI has not been clarified. In this paper, we critically discuss and compare the safety and efficacy of different strategies for CR in patients with STEMI and MVD using a Bayesian network meta-analysis including all previous randomized controlled trials (RCTs). In Bayesian network meta-analysis of 13 RCTs, culprit-only PCI was associated with higher risk of major adverse cardiac events (MACE), compared with angiography-guided or fractional flow reserve (FFR)-guided CR strategies. However, there was no significant difference between angiography-guided and FFR-guided CR strategies in the risk of MACE and its individual components including all-cause death, cardiac death, myocardial infarction (MI), and revascularization. These evidence support that both angiography-guided and FFR-guided complete revascularization strategies would be reasonable treatment option in patients with STEMI and MVD. If the non-culprit lesion is severe on visual assessment, angiography-guided PCI can be considered. If the non-culprit lesion is intermediate in severity or unclear based on visual assessment, FFR-guided strategy can be used as a reliable and objective tool, providing similar benefits with less stents compared with an angiographyguided strategy. Further RCT is needed to evaluate direct comparison between angiographyguided and FFR-guided CR strategies in patients with STEMI and MVD. Ongoing FRAMEAMI trial (NCT02715518) will provide more evidence regarding this issue.

The Effects of Preoperative Aspirin on Coronary Artery Bypass Surgery: a Systematic Meta-Analysis

BACKGROUND AND OBJECTIVES: Aspirin plays an important role in the maintenance of graft patency and the prevention of thrombotic event after coronary artery bypass graft surgery (CABG). However, the use of preoperative aspirin is still under debate due to the risk of bleeding. METHODS: From PubMed, EMBASE, and Cochrane Central Register of Controlled Trials, data were extracted by 2 independent reviewers. Meta-analysis using random effect model was performed. RESULTS: We performed a systemic meta-analysis of 17 studies (12 randomized controlled studies and 5 non-randomized registries) which compared clinical outcomes of 9,101 patients who underwent CABG with or without preoperative aspirin administration. Preoperative aspirin increased chest tube drainage (weighted mean difference 177.4 mL, 95% confidence interval [CI], 41.3–313.4; p=0.011). However, the risk of re-operation for bleeding was not different between the preoperative aspirin group and the control group (3.2% vs. 2.4%; odds ratio [OR], 1.23; 95% CI, 0.94–1.60; p=0.102). There was no difference in the rates of all-cause mortality (1.6% vs. 1.5%; OR, 0.98; 95% CI, 0.64–1.49; p=0.920) and myocardial infarction (MI) (8.7% vs. 10.4%; OR, 0.83; 95% CI, 0.66–1.04; p=0.102) between patients with and without preoperative aspirin administration. CONCLUSIONS: Although aspirin increased the amount of chest tube drainage, it was not associated with increased risk of re-operation for bleeding. In addition, the risks of early postoperative all-cause mortality and MI were not reduced by using preoperative aspirin.

Gender difference in the association between brachial-ankle pulse wave velocity and cardiovascular risk scores

BACKGROUND/AIMS@#Although brachial-ankle pulse wave velocity (baPWV) has been validated as a novel method to predict the cardiovascular risk in general population, the relevance of baPWV to the traditional risk scores has not been clearly revealed. This study investigated the relationship between baPWV and four different cardiovascular risk-predicting scores in men and women.@*METHODS@#A total of 539 subjects (58.1 ± 12.2 years, 50.1% men) without cardiovascular disease (CVD) who underwent health examinations including baPWV measurement were retrospectively analyzed. Four cardiovascular risk scores (Framingham risk score [FRS; 1998], Adult Treatment Panel [ATP] III revised FRS [2002], generalized FRS [2008], and American College of Cardiology/American Heart Association [ACC/AHA] CVD risk [2013]) were calculated in each subject.@*RESULTS@#In a total population, baPWV was moderately correlated with four cardiovascular risk scores (r = 0.577 for FRS; r = 0.594 for ATP III revised FRS; r = 0.589 for generalized FRS; r = 0.571 for ACC/AHA CVD risk; p < 0.001 for each). These correlations were stronger in women than in men (r = 0.649 vs. 0.451 for FRS; r = 0.719 vs. 0.411 for ATP III revised FRS; r = 0.735 vs. 0.540 for generalized FRS; r = 0.699 vs. 0.552 for ACC/AHA CVD risk; p for gender difference ≤ 0.005 for each).@*CONCLUSIONS@#In middle-aged and elderly Koreans without CVD, baPWV was identified as having a moderately positive correlation with four different risk scores. The correlation was stronger in women than in men, implying the better performance of baPWV in women for predicting cardiovascular risk of healthy population.

The Effects of Preoperative Aspirin on Coronary Artery Bypass Surgery: a Systematic Meta-Analysis

BACKGROUND AND OBJECTIVES@#Aspirin plays an important role in the maintenance of graft patency and the prevention of thrombotic event after coronary artery bypass graft surgery (CABG). However, the use of preoperative aspirin is still under debate due to the risk of bleeding.@*METHODS@#From PubMed, EMBASE, and Cochrane Central Register of Controlled Trials, data were extracted by 2 independent reviewers. Meta-analysis using random effect model was performed.@*RESULTS@#We performed a systemic meta-analysis of 17 studies (12 randomized controlled studies and 5 non-randomized registries) which compared clinical outcomes of 9,101 patients who underwent CABG with or without preoperative aspirin administration. Preoperative aspirin increased chest tube drainage (weighted mean difference 177.4 mL, 95% confidence interval [CI], 41.3–313.4; p=0.011). However, the risk of re-operation for bleeding was not different between the preoperative aspirin group and the control group (3.2% vs. 2.4%; odds ratio [OR], 1.23; 95% CI, 0.94–1.60; p=0.102). There was no difference in the rates of all-cause mortality (1.6% vs. 1.5%; OR, 0.98; 95% CI, 0.64–1.49; p=0.920) and myocardial infarction (MI) (8.7% vs. 10.4%; OR, 0.83; 95% CI, 0.66–1.04; p=0.102) between patients with and without preoperative aspirin administration.@*CONCLUSIONS@#Although aspirin increased the amount of chest tube drainage, it was not associated with increased risk of re-operation for bleeding. In addition, the risks of early postoperative all-cause mortality and MI were not reduced by using preoperative aspirin.

Association of Complex Fractionated Electrograms with Atrial Myocardial Thickness and Fibrosis

BACKGROUND AND OBJECTIVES: Although ablation of complex fractionated atrial electrograms (CFAE) in atrial fibrillation (AF) is one of the strategies for atrial substrate modification, the mechanism behind CFAE as an electrophysiological substrate remains unclear. We investigated structural differences between CFAE sites and their matched non-CFAE sites by comparing their histopathologic characteristics in canine AF models. METHODS: Atrial electrograms of four dogs were obtained from the epicardial site. AF was induced through burst atrial pacing at 600 bpm for 30 min. CFAE sites were identified during AF according to patterns visualized on the electrograms, and their matched non-CFAE sites were selected in the adjacent region, within 5 mm of each CFAE site. Tissues were harvested from CFAE sites and their matched non-CFAE sites at various locations in both atria. Histopathologic differences were identified between CFAE and non-CFAE sites. RESULTS: A total of 24 atrial tissues (12 with CFAE, 12 with non-CFAE) were evaluated. The atrial myocardium was significantly thicker at CFAE sites (1757.5±560.5 µm) than at non-CFAE sites (1279.5±337.2 µm) (p=0.036). At CFAE sites, it was filled with a significantly larger amount of fibrotic tissue than at non-CFAE sites (22.8±6.9% versus 7.2±4.7%, p < 0.001). Results were consistent across various tissue locations. The distribution of autonomic nerve innervation was similar between CFAE and non-CFAE sites. CONCLUSION: This study provides a better understanding of histological characteristics of CFAE sites, namely a thicker wall and greater amount of fibrosis. These findings may be associated with the development of CFAE and its pathophysiological contribution to AF.