Timing of heart failure development and clinical outcomes in patients with acute myocardial infarction.

Background and objectives: To investigate the clinical relevance of the timing of heart failure (HF) development on long-term outcome in patients with acute myocardial infarction (AMI). Materials and methods: A total of 1,925 consecutive AMI patients were divided into 4 groups according to the timing of HF development; HF at admission (group I, n = 627), de novo HF during hospitalization (group II, n = 162), de novo HF after discharge (group III, n = 98), no HF (group IV, n = 1,038). Major adverse cardiac events (MACE) defined as the development of death, re-hospitalization, recurrent MI or revascularization were evaluated. Results: HF was developed in 887 patients (46.1%) after an index AMI. HF was most common at the time of admission for AMI, but the development of de novo HF during hospitalization or after discharge was not uncommon. MACE was developed in 619 out of 1,925 AMI patients (31.7%). MACE was highest in group I, lowest in group IV, and significantly different among groups; 275 out of 627 patients (43.9%) in group I, 64 out of 192 patients (39.5%) in group II, 36 out of 98 patients (36.7%) in group III, and 235 out of 1,038 patients (22.6%) in group IV (P < 0.001). MACE free survival rates at 3 years were 56% in group I, 62% in group II, 64% in group III, and 77% in group IV (P < 0.001). Conclusions: HF was not uncommon and can develop at any time after an index AMI, and the development of HF was associated with poor prognosis. The earlier the HF has occurred after AMI, the poorer the clinical outcome was. To initiate the guideline directed optimal medical therapy, therefore, the development of HF should be carefully monitored even after the discharge from an index AMI.

COVID-19 vaccination-related myocarditis: a Korean nationwide study.

AIMS: A comprehensive nationwide study on the incidence and outcomes of COVID-19 vaccination-related myocarditis (VRM) is in need. METHODS AND RESULTS: Among 44 276 704 individuals with at least 1 dose of COVID-19 vaccination, the incidence and clinical courses of VRM cases confirmed by the Expert Adjudication Committee of the Korea Disease Control and Prevention Agency were analyzed. COVID-19 VRM was confirmed in 480 cases (1.08 cases per 100 000 persons). Vaccination-related myocarditis incidence was significantly higher in men than in women (1.35 vs. 0.82 per 100 000 persons, P < 0.001) and in mRNA vaccines than in other vaccines (1.46 vs. 0.14 per 100 000 persons, P < 0.001). Vaccination-related myocarditis incidence was highest in males between the ages of 12 and 17 years (5.29 cases per 100 000 persons) and lowest in females over 70 years (0.16 cases per 100 000 persons). Severe VRM was identified in 95 cases (19.8% of total VRM, 0.22 per 100 000 vaccinated persons), 85 intensive care unit admission (17.7%), 36 fulminant myocarditis (7.5%), 21 extracorporeal membrane oxygenation therapy (4.4%), 21 deaths (4.4%), and 1 heart transplantation (0.2%). Eight out of 21 deaths were sudden cardiac death (SCD) attributable to VRM proved by an autopsy, and all cases of SCD attributable to VRM were aged under 45 years and received mRNA vaccines. CONCLUSION: Although COVID-19 VRM was rare and showed relatively favorable clinical courses, severe VRM was found in 19.8% of all VRM cases. Moreover, SCD should be closely monitored as a potentially fatal complication of COVID-19 vaccination.

Antiarrhythmic Effect of Artemisinin in an Ex-vivo Model of Brugada Syndrome Induced by NS5806.

BACKGROUND AND OBJECTIVES: Brugada syndrome (BrS) is an inherited arrhythmia syndrome that presents as sudden cardiac death (SCD) without structural heart disease. One of the mechanisms of SCD has been suggested to be related to the uneven dispersion of transient outward potassium current (Ito) channels between the epicardium and endocardium, thus inducing ventricular tachyarrhythmia. Artemisinin is widely used as an antimalarial drug. Its antiarrhythmic effect, which includes suppression of Ito channels, has been previously reported. We investigated the effect of artemisinin on the suppression of electrocardiographic manifestations in a canine experimental model of BrS. METHODS: Transmural pseudo-electrocardiograms and epicardial/endocardial transmembrane action potentials (APs) were recorded from coronary-perfused canine right ventricular wedge preparations (n=8). To mimic the BrS phenotypes, acetylcholine (3 µM), calcium channel blocker verapamil (1 µM), and Ito agonist NS5806 (6-10 µM) were used. Artemisinin (100-150 µM) was then perfused to ameliorate the ventricular tachyarrhythmia in the BrS models. RESULTS: The provocation agents induced prominent J waves in all the models on the pseudo-electrocardiograms. The epicardial AP dome was attenuated. Ventricular tachyarrhythmia was induced in six out of 8 preparations. Artemisinin suppressed ventricular tachyarrhythmia in all 6 of these preparations and recovered the AP dome of the right ventricular epicardium in all preparations (n=8). J wave areas and epicardial notch indexes were also significantly decreased after artemisinin perfusion. CONCLUSIONS: Our findings suggest that artemisinin has an antiarrhythmic effect on wedge preparation models of BrS. It might work by inhibition of potassium channels including Ito channels, subsequently suppressing ventricular tachycardia/ventricular fibrillation.

Standard-Intensity Versus Low-Intensity Anticoagulation with Warfarin in Asian Patients with Atrial Fibrillation: A Multi-Center, Randomized Controlled Trial.

Anticoagulation with warfarin in Asian patients with atrial fibrillation (AF) often has been decreased as an international normalized ratio (INR) of prothrombin time 1.6-2.6 due to fear of bleeding, although universal criteria recommend an INR of 2.0-3.0. In this randomized, open-label trial, low-intensity anticoagulation (INR 1.6-2.6) was compared with standard-intensity anticoagulation (INR 2.0-3.0) with warfarin. A total 616 patients with AF and at least 1 risk factor for stroke were randomized to low-intensity anticoagulation (n = 308) and standard-intensity anticoagulation (n = 308) groups. The intention-to-treat analysis was performed to determine differences. The baseline characteristics of the two groups were comparable. New-onset stroke occurred in 2 patients (0.44% per year) in the low-intensity group and 5 patients (1.05% per year) in the standard-intensity group (HR 0.42, 95% CI 0.08-2.15). Major bleeding occurred in 4 patients (0.89% per year) in the low-intensity group and 5 patients (1.06% per year) in the standard-intensity group (HR 0.84, 95% CI 0.22-3.11). The rate of the net clinical outcome (composite of stroke, systemic embolism, major bleeding, and death) was 1.33% per year in the low-intensity group compared with 2.12% per year in the standard-intensity group (HR 0.63, 95% CI 0.23-1.72). In Asian patients with AF, clinical outcomes were not different between low-intensity and standard-intensity anticoagulation with warfarin.

Predictors of Progression of Tricuspid Regurgitation in Patients with Persistent Atrial Fibrillation.

Previous studies have shown that tricuspid regurgitation (TR) can be developed in patients with atrial fibrillation (AF) due to annular dilatation. This study aimed to investigate the incidence and predictors of the progression of TR in patients with persistent AF. A total of 397 patients (66.9±11.4 years, 247 men; 62.2%) with persistent AF were enrolled between 2006 and 2016 in a tertiary hospital, and 287 eligible patients with follow-up echocardiography were analyzed. They were divided into two groups according to TR progression (progression group [n=68, 70.1±10.7 years, 48.5% men] vs. non-progression group [n=219, 66.0±11.3 years, 64.8% men]). Among 287 patients in the analysis, 68 had worsening TR severity (23.7%). Patients in the TR progression group were older and more likely to be female. Patients with left ventricular ejection fraction <50% were less frequent in the progression group than those in the non-progression group (7.4% vs. 19.6%, p=0.018). Patients with mitral valve disease were more frequent in the progression group. Multivariate analysis with COX regression demonstrated independent predictors of TR progression, including left atrial (LA) diameter >54 mm (HR 4.85, 95%CI 2.23-10.57, p<0.001), E/e' (HR 1.05, 95%CI 1.01-1.10, p=0.027), and no use of antiarrhythmic agents (HR 2.20, 95%CI 1.03-4.72, p=0.041). In patients with persistent AF, worsening TR was not uncommon. The independent predictors of TR progression turned out to be greater LA diameter, higher E/e', and no use of antiarrhythmic agents.

A Case Report for Acute Myopericarditis After NVX-CoV2373 (Novavax®) COVID-19 Vaccination.

Post-vaccination myocarditis after administration of the NVX-CoV2373 coronavirus disease 2019 (COVID-19) vaccine has been reported in a limited population. We report the first biopsy-proven case of myopericarditis after administration of second dose of NVX-CoV2373 COVID-19 vaccine (Novavax®) in Korea. A 30-year-old man was referred to emergency department with complaints of chest pain and mild febrile sense for two days. He received the second dose vaccine 17 days ago. Acute myopericarditis by the vaccination was diagnosed by cardiac endomyocardial biopsy. He was treated with corticosteroid 1 mg/kg/day for 5 days and tapered for one week. He successfully recovered and was discharged on the 12th day of hospitalization. The present case suggests acute myopericarditis as a vaccination complication by Novavax® in Korea.

Clinical outcomes in patients with atrioventricular block undergoing pacemaker: 3-year follow-up.

PURPOSE: Left ventricular function can be affected by chronic ventricular pacing. Different right ventricular (RV) pacing sites have shown heterogeneous clinical outcomes. We investigated these factors in patients receiving permanent pacemaker (PPM) implants. METHODS: This multicenter, retrospective analysis of PPM use in South Korea, included all patients undergoing de novo transvenous PPM implantation for atrioventricular block from 2017 to 2019. Clinical characteristics, 12-lead electrocardiograms, echocardiography, and laboratory parameters were evaluated. Composite outcomes are defined by two coprimary endpoints: (1) hospitalizations and (2) cardiac death by heart failure during follow-up period. RESULTS: There were 167 patients (66 males; overall mean age 75.3 ± 11.9 years), divided into two groups according to the pacing site: 83 apical RV (RVA) vs. 84 septal RV (RVS). There were no significant baseline differences. Paced QRS duration (pQRSd) increased with RVA (168.5 ± 20.1 vs. 159.1 ± 16.3 ms; p < 0.001). Over a median 31-month follow-up, there were 15 hospitalizations and 2 deaths. More patients with RVA were hospitalized or died (16% vs. 5%, respectively; p = 0.049). In Cox proportional regression analysis, pQRSd (hazard ratio [HR] 1.046; 95% confidence interval [CI] 1.004-1.091; p = 0.033), and diastolic dysfunction (HR 7.343; 95% CI 2.035-26.494; p = 0.002) were independent predictors of composite clinical outcomes. CONCLUSIONS: RVS placement shortened the pQRSd and improved clinical outcomes. However, the determinants of these were pQRSd and diastolic dysfunction. Therefore, clinicians should try to shorten the pQRSd when implanting a PPM, and patients with diastolic dysfunction should be monitored intensively.

Characteristics and Clinical Outcomes of Cancer Patients who Developed Constrictive Physiology After Pericardiocentesis.

BACKGROUND AND OBJECTIVES: This study aimed to identify the characteristics and clinical outcomes of cancer patients who developed constrictive physiology (CP) after percutaneous pericardiocentesis. METHODS: One-hundred thirty-three cancer patients who underwent pericardiocentesis were divided into 2 groups according to follow-up echocardiography (CP vs. non-CP). The clinical history, imaging findings, and laboratory results, and overall survival were compared. RESULTS: CP developed in 49 (36.8%) patients after pericardiocentesis. The CP group had a more frequent history of radiation therapy. Pericardial enhancement and malignant masses abutting the pericardium were more frequently observed in the CP group. Fever and ST segment elevation were more frequent in the CP group, with higher C-reactive protein levels (6.6±4.3mg/dL vs. 3.3±2.5mg/dL, p<0.001). Pericardial fluid leukocytes counts were significantly higher, and positive cytology was more frequent in the CP group. In baseline echocardiography before pericardiocentesis, medial e' velocity was significantly higher in the CP group (8.6±2.1cm/s vs. 6.5±2.3cm/s, p<0.001), and respirophasic ventricular septal shift, prominent expiratory hepatic venous flow reversal, pericardial adhesion, and loculated pericardial fluid were also more frequent. The risk of all-cause death was significantly high in the CP group (hazard ratio, 1.53; 95% confidence interval,1.10-2.13; p=0.005). CONCLUSIONS: CP frequently develops after pericardiocentesis, and it is associated with poor survival in cancer patients. Several clinical signs, imaging, and laboratory findings suggestive of pericardial inflammation and/or direct malignant pericardial invasion are frequently observed and could be used as predictors of CP development.

Post-operative Atrial Fibrillation Impacts on Outcomes in Transcatheter and Surgical Aortic Valve Replacement.

Background: Atrial fibrillation (AF) in severe aortic stenosis (AS) has poor outcomes after transcatheter and surgical aortic valve replacement (TAVR and SAVR, respectively). We compared the incidence of AF after aortic valve replacement (AVR) according to the treatment method and the impact of AF on outcomes. Methods: We investigated the incidence of AF and clinical outcomes of AVR according to whether AF occurred after TAVR and SAVR after propensity score (PS)-matching for 1 year follow-up. Clinical outcomes were defined as death, stroke, and admission due to heart failure. The composite outcome comprised death, stroke, and admission due to heart failure. Results: A total of 221 patients with severe AS were enrolled consecutively, 100 of whom underwent TAVR and 121 underwent SAVR. The incidence of newly detected AF was significantly higher in the SAVR group before PS-matching (6.0 vs. 40.5%, P < 0.001) and after PS-matching (7.5 vs. 35.6%, P = 0.001). TAVR and SAVR showed no significant differences in outcomes except in terms of stroke. In the TAVR group, AF history did not affect the outcomes; however, in the SAVR group, AF history affected death (log rank P = 0.038). Post-AVR AF had a worse impact on admission due to heart failure (log rank P = 0.049) and composite outcomes in the SAVR group. Post-AVR AF had a worse impact on admission due to heart failure (log rank P = 0.008) and composite outcome in the TAVR group. Conclusion: Post-AVR AF could be considered as a predictor of the outcomes of AVR. TAVR might be a favorable treatment option for patients with severe symptomatic AS who are at high-risk for AF development or who have a history of AF because the occurrence of AF was more frequent in the SAVR group.

What is Standard Dose of Rivaroxaban in Elderly Asian Patients with Atrial Fibrillation: 20ms versus. 15mg?

Although there is no age criterion for rivaroxaban dose reduction, elderly patients with atrial fibrillation (AF) are often prescribed an off-label reduced dose. We aimed to evaluate whether age is a necessary criterion for rivaroxaban dose reduction in Korean patients with AF. Among 2208 patients who prescribed warfarin or rivaroxaban, 552 patients over 75 years without renal dysfunction (creatinine clearance >50 mL/min) were compared based on propensity score matching. The rivaroxaban group was further divided into a 20 mg (R20; on-label) and a 15 mg (R15; off-label). Primary net clinical benefit (NCB) was defined as the composite of stroke, systemic embolism, major bleeding, and all-cause mortality. Secondary NCB was defined as the composite of stroke, systemic embolism, and major bleeding. Patients were followed for 1 year, or until the first outcome occurrence. Both rivaroxaban groups had comparable efficacy compared with warfarin. However, both R20 (0.9% vs 7.4%, p = .014) and R15 (2.3% vs 7.4%, p = .018) had a significant reduction in major bleeding. There were no differences in efficacy or safety outcomes between R20 and R15. R20 had significantly reduced primary (hazard ratio [HR] 0.33, 95% confidence interval [CI]: 0.12-0.93) and secondary (HR 0.31, 95% CI: 0.10-0.93) NCBs compared with warfarin. However, primary and secondary NCBs were not reduced in R15. In real-world practice with elderly patients with AF, off-label rivaroxaban dose reduction to 15 mg conferred no benefits. Therefore, guideline-adherent rivaroxaban 20 mg is favorable in elderly Korean patients with AF.

Usefulness of Diastolic Function Score as a Predictor of Long-Term Prognosis in Patients With Acute Myocardial Infarction.

Background: Left ventricular diastolic function (LVDF) evaluation using a combination of several echocardiographic parameters is an important predictor of adverse events in patients with acute myocardial infarction (AMI). To date, the clinical impact of each individual LVDF marker is well-known, but the clinical significance of the sum of the abnormal diastolic function markers and the long-term clinical outcome are not well-known. This study aimed to investigate the usefulness of LVDF score in predicting clinical outcomes of patients with AMI. Methods: LVDF scores were measured in a 2,030 patients with AMI who underwent successful percutaneous coronary intervention from 2012 to 2015. Four LVDF parameters (septal e' ≥ 7 cm/s, septal E/e' ≤ 15, TR velocity ≤ 2.8 m/s, and LAVI ≤ 34 ml/m2) were used for LVDF scoring. The presence of each abnormal LVDF parameter was scored as 1, and the total LVDF score ranged from 0 to 4. Mortality and hospitalization due to heart failure (HHF) in relation to LVDF score were evaluated. To compare the predictive ability of LVDF scores and left ventricular ejection fraction (LVEF) for mortality and HHF, receiver operating characteristic (ROC) curve and landmark analyses were performed. Results: Over the 3-year clinical follow-up, all-cause mortality occurred in 278 patients (13.7%), while 91 patients (4.5%) developed HHF. All-cause mortality and HHF significantly increased as LVDF scores increased (all-cause mortality-LVDF score 0: 2.3%, score 1: 8.8%, score 2: 16.7%, score 3: 31.8%, and score 4: 44.5%, p < 0.001; HHF-LVDF score 0: 0.6%, score 1: 1.8%, score 2: 6.3%, score 3: 10.3%, and score 4: 18.2%, p < 0.001). In multivariate analysis, a higher LVDF score was associated with significantly higher adjusted hazard ratios for all-cause mortality and HHF. In landmark analysis, LVDF score was a better predictor of long-term mortality than LVEF (area under the ROC curve: 0.739 vs. 0.640, p < 0.001). Conclusion: The present study demonstrated that LVDF score was a significant predictor of mortality and HHF in patients with AMI. LVDF scores are useful for risk stratification of patients with AMI; therefore, careful monitoring and management should be performed for patients with AMI with higher LVDF scores.

Benefit of Extracorporeal Membrane Oxygenation before Revascularization in Patients with Acute Myocardial Infarction Complicated by Profound Cardiogenic Shock after Resuscitated Cardiac Arrest.

BACKGROUND AND OBJECTIVES: The study sought to investigate the impact of early extracorporeal membrane oxygenation (ECMO) support before revascularization in patients with acute myocardial infarction (AMI) complicated by profound cardiogenic shock after resuscitated cardiac arrest. It is difficult to determine optimal timing of ECMO in patients with AMI complicated by profound cardiogenic shock after resuscitated cardiac arrest. METHODS: Among 116,374 patients experiencing out-of-hospital cardiac arrest in South Korea, a total of 184 resuscitated patients with AMI complicated by profound cardiogenic shock, and who were treated successfully with percutaneous coronary intervention (PCI) and ECMO, were enrolled. Patients were divided into 2 groups according to the timing of ECMO: pre-PCI ECMO (n=117) and post-PCI ECMO (n=67). We compared 30-day mortality between the 2 groups. RESULTS: In-hospital mortality was 78.8% in the entire study population and significantly lower in the pre-PCI ECMO group (73.5% vs. 88.1%, p=0.020). Thirty-day mortality was also lower in the pre-PCI ECMO group compared to the post-PCI ECMO group (74.4% vs. 91.0%; adjusted hazard ratio [HR], 0.66; 95% confidence interval [CI], 0.47-0.93; p=0.017). Shockable rhythm at the emergency room (HR, 0.57; 95% CI, 0.36-0.91; p=0.019) and successful therapeutic hypothermia (HR, 0.40; 95% CI, 0.23-0.69; p=0.001) were also associated with improved 30-day survival. CONCLUSIONS: ECMO support before revascularization was associated with an improved short-term survival rate compared to ECMO after revascularization in patients with AMI complicated by profound cardiogenic shock after resuscitated cardiac arrest.

Gender Difference of Cardiac Remodeling in University Athletes: Results from 2015 Gwangju Summer Universiade.

BACKGROUND AND OBJECTIVES: There is little data about cardiac geometry in highly trained young athletes, especially female specific changes. We investigated gender difference on exercise induced cardiac remodeling (EICR) in highly trained university athletes. METHODS: A total of 1,185 university athletes divided into 2 groups; female (n=497, 22.0±2.3 years) vs. male (n=688, 22.6±2.4 years). Remodeling of the left ventricle (LV), left atrium (LA), right ventricle (RV), and any cardiac chamber were compared. RESULTS: LV, LA, RV, and any remodeling was found in 156 (13.2%), 206 (17.4%), 82 (6.9%), and 379 athletes (31.9%), respectively. LV, LA, and any remodeling were more common in male than female athletes (n=53, 12.1% vs. n=103, 15.5%, p=0.065), (n=65, 13.1% vs. n=141, 20.5%, p<0.001), (n=144, 30.0% vs. n=235, 34.2%, p=0.058), respectively, whereas RV remodeling was significantly more common in female than male athletes (n=56, 11.3% vs. n=26, 3.8%, p<0.001). Interestingly, the development of LV, LA, and RV remodeling were not overlapped in many of athletes, suggesting different mechanism of EICR according to cardiac chamber. Various predictors including sports type, heart rate, muscle mass, fat mass, body surface area, and training time were differently involved in cardiac remodeling, and there were gender differences of these predictors for cardiac remodeling. CONCLUSIONS: EICR was common in both sex and was independently developed among cardiac chambers in highly trained university athletes. LV and LA remodeling were common in males, whereas RV remodeling was significantly more common in females demonstrating gender difference in EICR. The present study also demonstrated gender difference in the predictors of EICR.

Right Ventricular Longitudinal Conduction Delay in Patients with Brugada Syndrome.

BACKGROUND: The mechanism of Brugada syndrome (BrS) is still unclear, with different researchers favoring either the repolarization or depolarization hypothesis. Prolonged longitudinal activation time has been verified in only a small number of human right ventricles (RVs). The purpose of the present study was to demonstrate RV conduction delays in BrS. METHODS: The RV outflow tract (RVOT)-to-RV apex (RVA) and RVA-to-RVOT conduction times were measured by endocardial stimulation and mapping in 7 patients with BrS and 14 controls. RESULTS: Patients with BrS had a longer PR interval (180 ± 12.6 vs. 142 ± 6.7 ms, P = 0.016). The RVA-to-RVOT conduction time was longer in the patients with BrS than in controls (stimulation at 600 ms, 107 ± 9.9 vs. 73 ± 3.4 ms, P = 0.001; stimulation at 500 ms, 104 ± 12.3 vs. 74 ± 4.2 ms, P = 0.037; stimulation at 400 ms, 107 ±12.2 vs. 73 ± 5.1 ms, P = 0.014). The RVOT-to-RVA conduction time was longer in the patients with BrS than in controls (stimulation at 500 ms, 95 ± 10.3 vs. 62 ± 4.1 ms, P = 0.007; stimulation at 400 ms, 94 ±11.2 vs. 64 ± 4.6 ms, P = 0.027). The difference in longitudinal conduction time was not significant when isoproterenol was administered. CONCLUSION: The patients with BrS showed an RV longitudinal conduction delay obviously. These findings suggest that RV conduction delay might contribute to generate the BrS phenotype.

The change in high-sensitivity troponin-T as a risk factor for significant coronary stenosis in patients with acute coronary syndrome.

BACKGROUND/AIMS: High-sensitivity cardiac troponin (hs-TnT) assays detect very low levels of cardiac troponin. This study examined the interval change between initial and subsequent hs-TnT levels and evaluated its ability to predict significant coronary stenosis. METHODS: The study analyzed 163 patients who presented with acute coronary syndrome (ACS) and underwent coronary angiography (CAG) between April 2014 and May 2018. The 0 and 3-hour hs-TnT were checked. The patients were subdivided into positive (n = 32) and negative (n = 131) interval change groups. The presence of significant coronary artery stenosis on CAG in the two groups was compared. RESULTS: The positive interval change group was older and had higher 0 and 3-hour hs-TnT and blood glucose levels than the negative interval change group. Significant coronary stenosis was more common in the positive interval change group than in the negative interval change group (68.8% vs. 23.7%, p = 0.001). However, vasospasm was more common in the negative interval change group (6.3% vs. 31.3%, p = 0.003). The positive interval change group had higher rates of bifurcation lesions and received more percutaneous coronary intervention. In multivariate analysis, age, interval change of serial hs-TnT and diabetes mellitus were independent predictors of significant coronary artery stenosis. CONCLUSION: This study identified a relationship between the serial change in cardiac biomarkers and the presence of significant coronary stenosis in patients with ACS. Serial hs-TnT change was associated with real angiographic stenosis in patients with ACS.

Defibrillation threshold testing during implantable cardioverter defibrillator implantation: 5-year follow-up.

PURPOSE: Defibrillation threshold (DFT) testing is a routine practice in some Asian countries for patients receiving an implantable cardioverter defibrillator (ICD). However, there are few long-term data about the necessity of intraoperative DFT testing in an Asian population. We investigated the safety of DFT testing and the long-term clinical outcomes in Asian patients undergoing ICD implantation. METHODS: All patients undergoing de novo transvenous ICD implantation were randomized to undergo periprocedural DFT testing. The study included 67 patients (50 males; 51.5 ± 16.9 years) who underwent ICD implantation with (n = 33) or without (n = 34) intraoperative DFT testing between March 2012 and February 2014. We compared first-shock success, composite safety end points (the sum of complications recorded at 30 days), arrhythmic death, and all-cause mortality. RESULTS: The baseline clinical characteristics and the procedural-related adverse event rate (3.0% with DFT vs. 0% with non-DFT, p = 0.214) did not differ between groups. The programmed output of the first shock was lower in the DFT testing group (22.9 ± 4.4 J vs. 25.3 ± 5.4 J, p = 0.007). However, there were no significant differences between groups for all-cause mortality (12.1% vs. 17.6%, p = 0.526) or first-shock success rate for ventricular arrhythmia (100% vs. 88.2%, p = 0.471). CONCLUSIONS: There were no between-group differences in periprocedural safety, complications, and long-term clinical outcomes. Our results suggest that DFT testing in Asian patients allows reduction of the programmed output of the first shock, but does not affect long-term clinical outcomes.

Positive chronotropic effects of theophylline and cilostazol in patients with symptomatic sick sinus syndrome who have declined permanent pacing.

Pacemakers are more commonly recommended than theophylline for sick sinus syndrome (SSS) treatment. The positive effects of cilostazol on bradyarrhythmias also have been reported. However, no comparison of cilostazol and theophylline has been previously reported found. We retrospectively enrolled SSS patients, who refused a pacemaker implantation. Theophylline or cilostazol was administered, and the heart rate (HR) was evaluated in 4-8 weeks using a digital sphygmomanometer and the electrocardiogram (ECG). A 200-400 mg of theophylline or 100-200 mg of cilostazol were administered per day in 50 and 30 patients, respectively. The baseline HR was 54.8 ± 13.5 beats per minute (bpm) on using sphygmomanometry and 51.9 ± 11.8 bpm using the ECG. In the theophylline group, the HR increased by 12.0 ± 16.3 bpm by sphygmomanometry (P < 0.001) and 8.4 ± 12.0 bpm by the ECG (P < 0.001). In the cilostazol group, the HR increased by 16.8 ± 13.9 bpm by sphygmomanometry (P < 0.001) and 12.4 ± 13.4 bpm using the ECG (P < 0.001). In 15 of the 50 theophylline patients, the medication was switched to cilostazol. The HR increased from 61.4 ± 13.8 bpm to 64.0 ± 12.6 bpm (P = 0.338). Symptoms such as dyspnea, chest discomfort, dizziness, and syncope significantly improved after the administration of the medications. There were no significant differences in the improvement in the symptoms except for dizziness between the two agents. Cilostazol was as effective as theophylline for increasing the HR in SSS patients.

Clinical impact of echocardiography-defined pulmonary hypertension on the clinical outcome in patients with multiple myeloma.

Pulmonary hypertension (PH) is a complication of multiple myeloma (MM); however, the clinical outcomes and prognosis are relatively not well known. We aimed to investigate the risk factors of transthoracic echocardiography-defined PH and its impact on the clinical outcome in patients with MM.A retrospective study was performed using data from the Chonnam National University Hwasun Hospital database for patients who underwent transthoracic echocardiography (TTE) within 1 month of the MM diagnosis between January 2007 and December 2017. PH was defined as an estimated right ventricular systolic pressure (RVSP) > 40 mmHg. A total of 390 patients were included. TTE-defined PH was observed in 107 patients (27%). During the follow-up period (median, 688 days), all-cause death was noted for 134 patients (34.4%). In the Kaplan-Meier survival analysis, the cumulative overall survival and cardiovascular death-free survival rates were significantly lower in the PH group than in the non-PH group (P < .001). In the propensity score-matched population, RVSP > 40 mmHg on TTE and history of congestive heart failure (CHF) were identified as the significant independent predictors of all-cause and cardiovascular death.This study reports that the prevalence of TTE-defined PH is higher in patients with MM than in the general population. Moreover, TTE-defined PH and a history of CHF are the independent prognostic factors for all-cause and cardiovascular death in patients with MM. These results highlight the risk of associated cardiovascular disease in patients with MM and emphasize the importance of management strategies that prevent the deterioration of cardiac function.

Transmural conduction time in an early repolarization syndrome model.

In the pathological aspect of J wave syndrome, delayed depolarization is defined as the difference in local conduction velocity of the ventricular myocardium. If polymorphic ventricular tachycardia is induced without local conduction velocity heterogeneity, this contradicts the delayed depolarization theory. In the present study, the transmural conduction time at was evaluated at several transmural locations in a canine early repolarization model. The transmural pseudo-electrocardiogram and endocardial/epicardial action potentials were recorded from coronary-perfused canine left ventricular wedge preparations (n=18). The Ito agonist NS5806 (9-10 µM), Ca2+ channel blocker verapamil (2 µM) and acetylcholine (ACh) (2 µM) were used to pharmacologically mimic early repolarization syndrome genotypes. The transmural conduction times were measured at five fixed epicardial unipolar electrodes before and after the perfusion of provocative agents. The transmural conduction time was defined as the time from endocardial stimulation to the maximal negative deflection (dV/dt) of the endocardial electrogram at the unipolar electrode. Polymorphic ventricular tachycardia developed in 14/18 preparations. In the transmembrane action potentials, there was no definite delayed phase 0 upstroke in any induced polymorphic ventricular tachycardia preparations. In all preparations, the transmural conduction time increased significantly after perfusing the Ito agonist NS5806, verapamil and Ach; however, the increase was only 2.6±0.4 msec, and dispersion of the transmural conduction time did not exhibit significant heterogeneity (7.16±0.93 vs. 7.76±1.21 msec; P=0.240). In the early repolarization model, polymorphic ventricular tachycardia was induced without any regional conduction velocity heterogeneity. This finding suggests that local depolarization heterogeneity would not be a major contributor to the generation of ventricular arrhythmia in the early repolarization syndrome wedge preparation model.

Left atrial longitudinal strain as a predictor of Cancer therapeutics-related cardiac dysfunction in patients with breast Cancer.

BACKGROUND: We investigated the usefulness of the left atrial (LA) strain measurement on the prediction of upcoming cancer therapeutics-related cardiac dysfunction (CTRCD) after trastuzumab therapy in patients with breast cancer who did not develop CTRCD after chemotherapy. METHODS: A total of 72 females with breast cancer who did not develop CTRCD after chemotherapy and underwent additional trastuzumab therapy were divided into CTRCD (n = 13) and no CTRCD group (n = 59). Echocardiographic measurements including left ventricular global longitudinal strain (LVGLS) and peak atrial longitudinal strain (PALS) decline were compared. RESULTS: CTRCD was identified in 13 patients (18.1%) after additional trastuzumab therapy. Baseline echocardiographic findings were not different. After the completion of chemotherapy, conventional echocardiographic parameters were not different, but PALS decline (15.0 ± 4.7 vs. 8.9 ± 3.2%, p < 0.001) and LVGLS decline (10.5 ± 1.3 vs. 9.1 ± 1.1%, p = 0.002) were significantly greater in CTRCD than in no CTRCD group. PALS decline at the time of chemotherapy completion could predict future CTRCD after trastuzumab therapy with better sensitivity and specificity (cutoff value 11.79%, sensitivity 76.9% and specificity 81.4%) than LVGLS decline (cutoff value 9.9%, sensitivity 69.2% and specificity 78.0%). CONCLUSIONS: PALS or LVGLS decline developed before developing overt CTRCD after chemotherapy for breast cancer, and PALS decline showed better sensitivity and specificity in predicting future CTRCD than LVGLS decline. Serial measurement of PALS can be used as a useful parameter in the prediction of future CTRCD.