The characteristic of an abnormal p-wave axis in patients with atrial fibrillation.

BACKGROUNDS: An adverse increased risk of atrial fibrillation (AF) can be detected by measuring the p-wave indices, including prolonged p-wave duration, the PR interval, abnormal p-wave terminal force, and abnormal p-wave axis (aPWA). Our purpose was to characterize the AF patient population with an aPWA and to identify whether the aPWA was associated with recurrence after catheter ablation of AF. METHODS: This study retrospectively included 249 patients with AF who underwent catheter ablation in our hospital from October 2015 to May 2019. We measured the p-wave indices and left atrial cavity size (LAVI) before the catheter ablation. A logistic regression analysis was performed to analyze the concurrent effects of various factors on the prevalence of AF recurrence over 12 months after the ablation. RESULTS: An aPWA was observed in 35 patients (14%). There were significantly more patients with an aPWA in the non-PAF than PAF patients (26% versus 7%, p < 0.001). The patients with an aPWA had a significantly larger LAVI values (37 ± 12 versus 45 ± 11 ml/m2, p = 0.016). In a multivariate analysis, an aPWA (odds ratio, 4.27; 95% confidence interval, 1.75-10.4; p = 0.001) and the LAVI (odds ratio, 1.04; 95% confidence interval, 1.00-1.08; p = 0.032) were independently associated with recurrence after catheter ablation. CONCLUSIONS: Our results demonstrated that measuring the aPWA in patients with atrial fibrillation before ablation was useful for identifying patients at a higher risk of recurrence after catheter ablation of AF.

Subacute Stent Thrombosis After Primary Percutaneous Coronary Intervention in a Middle-Aged Anabolic Steroid-Abusing Bodybuilder.

A 54-year-old male bodybuilder who was abusing anabolic steroids developed an acute ST-segment elevation myocardial infarction after strenuous strength training. Despite optimal use of dual antiplatelet therapy, on day 4 after primary coronary stenting, the patient suffered another acute coronary event due to subacute thrombosis, potentially pre-disposed by anabolic steroid use. (Level of Difficulty: Intermediate.).

Clinical predictors for bradycardia and supraventricular tachycardia necessitating therapy in patients with unexplained syncope monitored by insertable cardiac monitor.

BACKGROUND: Insertable cardiac monitors (ICMs) improve diagnostic yield in patients with unexplained syncope. The most of cardiac syncope is arrhythmic causes include paroxysmal bradycardia and supraventricular tachycardia (SVT) in patients with unexplained syncope receiving ICM. Predictors for bradycardia and SVT that necessitate therapy in patients with unexplained syncope are not well known. HYPOTHESIS: This study aimed to investigate predictors of bradycardia and SVT necessitating therapy in patients with unexplained syncope receiving ICMs. METHODS: We retrospectively reviewed medical records of consecutive patients who received ICMs to monitor unexplained syncope. We performed Cox's stepwise logistic regression analysis to identify significant independent predictors for bradycardia and SVT. RESULTS: One hundred thirty-two patients received ICMs to monitor unexplained syncope. During the 17-month follow-up period, 19 patients (14%) needed pacemaker therapy for bradycardia; 8 patients (6%) received catheter ablation for SVT. The total estimated diagnostic rates were 34% and 48% at 1 and 2 years, respectively. Stepwise logistic regression analysis indicated that syncope during effort (odds ratio [OR] = 3.41; 95% confidence interval [CI], 1.21 to 9.6; p = .02) was an independent predictor for bradycardia. Palpitation before syncope (OR = 9.46; 95% CI, 1.78 to 50.10; p = .008) and history of atrial fibrillation (OR = 10.1; 95% CI, 1.96 to 52.45; p = .006) were identified as significant independent predictors for SVT. CONCLUSION: Syncope during effort, and palpitations or history of atrial fibrillation were independent predictors for bradycardia and for SVT. ICMs are useful devices for diagnosing unexplained syncope.

Collateral pulmonary vein after catheter ablation therapy for atrial fibrillation.

A patient with previous catheter ablation therapy for atrial fibrillation was examined for an abnormal shadow on a chest radiograph. ECG-gated multidetector CT clearly showed the left upper pulmonary vein connected with the left inferior pulmonary vein. We hypothesize an intrapulmonary venous connection as a collateral.

A case of takotsubo cardiomyopathy developing ventricular fibrillation after a pacemaker implantation.

Pacemaker implantations are minimally invasive procedures commonly used for patients with bradycardic arrhythmias. Takotsubo cardiomyopathy, which is usually induced by life-threatening stress hardly ever occurs after this minimally invasive procedure. Here, we experienced a patient who developed takotsubo cardiomyopathy leading to ventricular fibrillation the day after a pacemaker implantation. At that time, a cardiac echocardiogram and left ventriculogram revealed hypercontraction of the base of the heart and a decreased contraction of the apex. A coronary angiogram revealed no significant coronary stenosis. Ten days later, the electrocardiogram findings normalized, and an echocardiogram revealed that the left ventricular function had fully recovered. Therefore, we diagnosed this patient with takotsubo cardiomyopathy. In general, pacemaker implantations are routine procedures and fatal complications are low. We report a case that developed potentially fatal complications after a pacemaker implantation. .

Can an increase in the pulmonary vein volume measured by three dimensional computed tomography predict the presence of atrial fibrillation?

BACKGROUND: Left atrial (LA) dilation is associated with morbidity of atrial fibrillation (AF). However, little is known about pulmonary vein (PV) dilation. PURPOSE: We investigated the PV volume in the patients with AF. METHODS AND RESULTS: We performed 3dimensional computed tomography (3DCT) in 155 patients and divided them into three groups: 19 patients without AF (non-AF group, mean age 66 ± 12 years), 50 with paroxysmal AF (PAF group, mean age 67 ± 8 years) and 24 with persistent AF (PeAF group, mean age 64 ± 10 years). The absence of AF was diagnosed in patients with a cardiac implantable electronic device for at least 1 year (mean: 59 ± 37 months). We determined the PV volume as the total volume from the orifice to the first branch of each PV. According to the echocardiographic data, the LA dimension (LAD) and LA volume index (LAVI) were largest in the PeAF group followed by the PAF and non-AF group. According to the morphometric data obtained on 3D-CT, the PV volume was similar in PeAF and PAF groups but significantly smaller in the non-AF group (median value: 24 vs 21 vs 14 mL, respectively). According to the receiver operating characteristic curve analysis, the area under the curve for the PV volume in the presence of AF was 0.80, and the optimum cut-off value was 17 mL (sensitivity 74%, specificity 80%). CONCLUSION: The PV volume might be useful for predicting the presence of AF before increases in the LAD and LAVI on echocardiography.

High-frequency power within the QRS complex in ischemic cardiomyopathy patients with ventricular arrhythmias: Insights from a clinical study and computer simulation of cardiac fibrous tissue.

BACKGROUND: The distribution of frequency power (DFP) within the QRS complex (QRS) is unclear. This study aimed to investigate the DFP within the QRS in ischemic cardiomyopathy (ICM) with lethal ventricular arrhythmias (L-VA). A computer simulation was performed to explore the mechanism of abnormal frequency power. METHODS: The study included 31 ICM patients with and without L-VA (n = 10 and 21, respectively). We applied the continuous wavelet transform to measure the time-frequency power within the QRS. Integrated time-frequency power (ITFP) was measured within the frequency range of 5-300 Hz. The simulation model consisted of two-dimensional myocardial tissues intermingled with fibroblasts. We examined the relation between frequency power calculated from the simulated QRS and the fibroblast-to-myocyte ratio (r) of the model. RESULTS: The frequency powers significantly increased from 180 to 300 Hz and from 5 to 15 Hz, and also decreased from 45 to 80 Hz in patients with ICM and L-VA compared with the normal individuals. They increased from 110 Hz to 250 Hz in ICM alone. In the simulation, the high-frequency power increased when the ratio (r) were 2.0-2.5. Functional reentry was initiated if the ratio (r) increased to 2.0. CONCLUSIONS: Abnormal higher-frequency power (180-300 Hz) may provide arrhythmogenic signals in ICM with L-VA that may be associated with the fibrous tissue proliferation.

Cardiopulmonary arrest due to persistent coronary spasm in a young woman. Are we properly diagnosing vasospastic angina?

Coronary spasm is a risk factor for acute myocardial infarction and sudden cardiac death. This is a case of a young female patient with cardiopulmonary arrest induced by coronary spasm on arrival at our hospital. There has been no case that prolonged spontaneous attack was confirmed in multi-vessels. This case demonstrates that persistent coronary spasm is lethal and an important cause of cardiopulmonary arrest even in young people. It is extremely important to detect patients with coronary spasm before the ischemic events associated with cardiopulmonary arrest occur.

Provoked coronary spasm predicts adverse outcome in patients with acute myocardial infarction: a novel predictor of prognosis after acute myocardial infarction.

OBJECTIVES: This study was conducted to examine the relationship between provoked coronary spasm and clinical course in patients with acute myocardial infarction (AMI). BACKGROUND: Coronary spasm has a pathogenetic role in the occurrence of AMI and progressive atherosclerosis. There is no report that focused on the prognostic significance of provoked coronary spasm in AMI patients. METHODS: Our group investigated 240 consecutive patients who underwent spasm-provocation tests using acetylcholine after AMI. Coronary spasm was defined as a transient total or subtotal occlusion of the luminal diameter. The patients were divided into 2 groups (positive group: n = 174, negative group: n = 66). RESULTS: The clinical courses of the 2 groups were compared at long-term follow up (mean, 43 months). Major adverse cardiac events (death, acute coronary syndrome, or revascularization) occurred in 82 patients (47.1%) in the positive group and 18 patients (27.3%) in the negative group (p = 0.0055). The frequency of major adverse cardiac event-free survival was significantly lower in the positive group than in the negative group (p = 0.0018). Provoked coronary spasm was a significant independent predictor of poor prognosis. CONCLUSIONS: Provoked coronary spasm predicts adverse outcome in AMI patients.

Time-frequency analysis of QRS complex with wavelet transform in patients with triple-vessel disease.

OBJECTIVE: Significant Q-wave is sometimes invisible in the patients with triple vessel disease (TVD) even though TVD is a serious coronary heart disease. We offer the preliminary method to analyze the time-frequency profile of QRS in TVD patients. METHODS: Electrocardiograms (ECG) band-pass filtered through 50 to 300Hz were recorded from the persons without heart diseases (Normal group; n=24), the patients with single vessel disease (SVD group; n=12) and TVD (TVD group; n=12) and saved into PC. For each subject, the time-frequency powers of ECG (lead II) were calculated by the continuous wavelet transform (CWT) with 40 frequency bands. They were integrated during QRS to get the integrated time-frequency powers (ITFP) for all the frequency bands. RESULTS: The ITFP at lower frequency range (90 Hz or less) were smaller in SVD and TVD groups, compared with normal group. The ITFP at higher frequency range (120 to 350 Hz) were larger in patients with recurrent heart failure due to TVD. The increase in ITFP at wider frequency bands was seen with and without significant Q waves. CONCLUSION: The present results that the increase in higher frequency power in TVD with recurrent heart failure may indicate the severity of myocardial damage, regardless of significant Q-wave.