Left atrial functions in the early period after cryoballoon ablation for paroxysmal atrial fibrillation.

PURPOSE: In patients with paroxysmal atrial fibrillation (PAF), functional changes are observed in the left atrium (LA) after pulmonary vein isolation (PVI) procedure. Although previous studies have investigated the altered mechanical functions of the LA with radiofrequency (RF) ablation, changes in the LA functions in the early period after cryoablation (CB-2) have not been clearly demonstrated. This study aims to explore the early periodical changes in mechanical functions of the LA in patients with PAF who underwent CB-2 based ablation through the help of echocardiographic methods which contain Doppler and strain parameters. METHODS: Consecutive 77 patients (mean age: 57.5 ±  11.2; 57% men) with PAF underwent CB-2 were prospectively analyzed. All patients were in sinus rhythm before and after the procedure. The LA dimensions, the LA reservoir strain, the LA atrial contractile strain and the LA conduit strain and left ventricular diastolic function parameters were evaluated by Doppler echocardiography before and 3 months after the procedure. RESULTS: Acute procedural success was achieved in all cases. No major complications were observed. LA reservoir strain and LA contractile strain showed significant recovery after the procedure. (28.3 ± 12.8 vs. 34.6 ± 13.8, p < .001 and -10.8 ± 7.9 vs. -13.9 ± 9.3, p = .014 respectively). No significant change was demonstrated in other echocardiographic parameters. CONCLUSION: Significant improvement in mechanical functions may occur even in the early period after cryoballoon ablation in patients with PAF.

Prognostic significance of addition of electrocardiographic findings to the MAGGIC heart failure risk score.

BACKGROUND: The Meta-analysis Global Group in Chronic Heart Failure (MAGGIC) is a scoring system that is easy to use in outpatient or inpatient settings and was developed to predict the survival of heart failure (HF) patients after hospitalization. AIM: This study aims to determine the prognostic significance of MAGGIC risk score combined with electrocardiography (ECG) parameters in decompensated patients with heart failure with reduced left ventricular ejection fraction (HFrEF) who were hospitalized for worsening HF. METHODS: A total of 562 HF patients with New York Heart Association (NYHA) II-IV functional class who were discharged after hospitalization for decompensated HF between 2013 and 2018 in a single center were included. MAGGIC risk scores of all participating patients were calculated according to baseline characteristics gathered using data from the initial hospitalization for HF. In addition, electrocardiographic findings of all patients were examined. RESULTS: During the follow-up period (4.5 ± 1.2 years) 177 patients died. MAGGIC scores were observed to be higher in non-survivors compared to surviving patients (28.69 ± 7.01 vs. 22.82 ± 6.05, p < 0.001). After a multivariate analysis, MAGGIC score (OR:1.090, p < 0.001), development of cardio-renal syndrome (OR:2.035, p < 0.001), presence of left bundle branch block (LBBB) (OR:1.931, p < 0.001), atrial fibrillation (AF) (OR:1.817, p < 0.001), and fragmented QRS (fQRS) (OR:1.671, p = 0.002) on ECG were found to be independent predictors of mortality. While the MAGGIC score was shown to predict mortality (AUC = 0.739), its predictive power was improved when combined with AF (AUC = 0.752), LBBB (AUC = 0.745), and fQRS (AUC = 0.757) respectively, as well as in the combined final model (MAGGIC score, AF, LBBB, fQRS) (AUC = 0.787). CONCLUSIONS: Our findings showed that addition of electrocardiographic findings to the MAGGIC heart failure risk score has prognostic significance in decompensated patients with HFrEF.

Effects of obesity on arrhythmic events and survival in patients with an implantable cardioverter defibrillator.

Background    Studies have shown that increased body weight and obesity may be associated with an increased risk of arrhythmic events. The aim of this study was to evaluate the effect of obesity on the risk of arrhythmic events, hospitalization, and death in patients who received implantable cardioverter defibrillator (ICD) therapy for primary or secondary prevention.Material and Methods    A single-center, prospective, observational study was conducted. Patients with body mass index (BMI) <30 kg / m2 were classified as non-obese, and patients with BMI ≥30 kg / m2 were classified as obese. The primary endpoints were arrhythmic events and device interventions. The secondary endpoints were all-cause mortality, cardiac mortality, cardiac rehospitalization, and a composite endpoint of mortality and hospitalization.Results    Among a total of 340 patients, 78.2 % were male, and 22.1 % were obese. The mean age was 60.9 yrs. Ventricular tachycardia (VT) was more frequent in non-obese patients (HR 0.57, [CI] 0.38-0.87, p=0.009). All-cause mortality and cardiac mortality in all patients tended to be more frequent in non-obese (HR 2.71, [CI] 0.93-7.93, p= 0.069 for all-cause mortality; HR 3.29, [CI] 0.97-11.17, p=0.056 for cardiac mortality). In the subgroup analysis, VT, all-cause mortality, and cardiac mortality were more common for non-obese patients in primary prevention and ischemic heart failure (HF) groups.Conclusion    While VT was more frequent in non-obese patients, VF, ICD appropriate shock, inappropriate shock, and antitachycardia pacing were similar in obese and non-obese patients. All-cause mortality and cardiac mortality were more frequent in non-obese patients.

Determining host factors contributing to disease severity in a family cluster of 29 hospitalized SARS-CoV-2 patients: Could genetic factors be relevant in the clinical course of COVID-19?

In this study, we report a large family cluster consisting of 29 genetically related patients hospitalized with coronavirus disease-2019 (COVID-19). We sought to determine the clinical characteristics relevant to the clinical course of COVID-19 by comparing the family cluster to unrelated patients with SARS-CoV-2 infection so that the presence of potential determinants of disease severity, other than traditional risk factors previously reported, could be investigated. Twenty-nine patient files were investigated in group 1 and group 2 was created with 52 consecutive patients with COVID-19 having age and gender compatibility. The virus was detected for diagnosis. The clinical, laboratory and imaging features of all patients were retrospectively screened. Disease course was assessed using records regarding outcome from patient files retrospectively. Groups were compared with respect to baseline characteristics, disease severity on presentation, and disease course. There was no difference between the two groups in terms of comorbidity and smoking history. In terms of inhospital treatment, use differed not significantly between two groups. We found that all 29 patients in the group 1 had severe pneumonia, 18 patients had severe pneumonia. Hospitalization rates, length of hospital stay, and transferred to intensive care unit were found to be statistically significantly higher in the group 1. In the present study, COVID-19 cases in the large family cluster were shown to have more severe disease and worse clinical course compared with consecutive patients with COVID-19 presenting to the same time. We believe further studies into potential genetic mechanisms of host susceptibility to COVID-19 should include such family clusters.

Macroscopic T-wave alternans in a patient presenting with hepatic encephalopathy.

Macroscopic T-wave alternans (TWA) is the beat-to-beat variation in the amplitude or shape of the T wave on a surface electrocardiogram (ECG) and known to be a harbinger of impending malignant ventricular arrhythmias such as polymorphic ventricular tachycardia. We herein report a case with hepatic encephalopathy, who developed TWA, followed by polymorphic ventricular tachycardia.

Tocilizumab challenge: A series of cytokine storm therapy experiences in hospitalized COVID-19 pneumonia patients.

To recognize the period of exaggerated cytokine response in patients with coronavirus disease 2019 (COVID-19) pneumonia, and to describe the clinical outcomes of using tocilizumab as a treatment option. The data of 12 adult COVID-19 pneumonia patients who were followed in the inpatient clinics of Biruni University Medical Faculty Hospital (Istanbul, Turkey) were retrospectively analyzed. Diagnostic tests, laboratory examinations, clinical findings, and computed tomography of the thorax imaging results were evaluated. A dramatic laboratory and clinical improvement was observed in 83% (10 out of 12) of patients after tocilizumab. In 17% (2 out of 12) of our patients, short-term ventilator support was required in the intensive care unit. The longest hospital stay was 18 days. However, in the end, all of our patients were discharged home with good health. Although arterial oxygen saturations (87.58 ± 3.12%) dropped in room air in the pre-tocilizumab period, post-tocilizumab they normalized in all patients (94.42 ± 1%). None of them had fever after tocilizumab treatment and the levels of C-reactive protein (13.08 ± 12.89) were almost within normal limits. Eosinophil values were quite low at the time of diagnosis (10 ± 17.06), but increased significantly post-tocilizumab (155.33 ± 192.69). There is currently no proven treatment for COVID-19 induced by novel coronavirus SARS-CoV-2. Based on our experience with twelve adult COVID-19 pneumonia patients, we can say that tocilizumab, an IL-6 inhibitor, is more beneficial in preventing the damage caused by excessive cytokine response in the body if administered at the right time and provides clinical and radiological recovery.

Management of periprocedural anticoagulant therapy: a novel individualized approach-a transeusophageal echocardiographic study.

Patients with non-valvular atrial fibrillation who are under chronic oral anticoagulant therapy (OAC) treatment frequently require interruption of OAC treatment. By examining the presence of left atrial/left atrial appendage (LA/LAA) thrombus or dense spontaneous echo contrast (SEC) with transesophageal echocardiography (TEE) we aimed to develop an individualized strategy. To test the validity of CHA2DS2VASc score based recommendations was our secondary purpose. In this prospective study patients with non-valvular atrial fibrillation on OAC therapy were included. Patients' baseline characteristics, CHA2DS2VASc and HASBLED scores, medications, type of invasive procedures and clinical events were recorded. Each patient underwent to TEE examination prior to the invasive procedure. Bridging anticoagulation was recommended only to patients with LA/LAA thrombus. We included 155 patients and mean CHA2DS2VASc score of the study population was 3.4 ± 1.4. Seventy-one of them had LA/LAA thrombi or SEC on TEE examination and bridging anticoagulation was applied. OAC treatment was not bridged in 8 of 11 patients with prior cerebrovascular accident and 17 of 31 patients with CHA2DS2VASc score of > 4. 57 of 124 patients with CHA2DS2VASc score of ≤ 4 required bridging anticoagulation. There were 14 major bleedings decided according to ISTH bleeding classification. Major bleeding was observed only in patients underwent to high-risk bleeding procedure. In conclusion CHA2DS2VASc score by itself is not enough for decision-making regarding ischemic risk. Furthermore, since major bleedings occurred only in patients underwent to high-risk bleeding surgery, TEE-based individualisation may be a feasible approach particularly for those with high thromboembolic risk undergoing high-bleeding risk procedure.

The clinical significance of premature atrial contractions: How frequent should they become predictive of new-onset atrial fibrillation.

BACKGROUND: Although previous studies reported frequent premature atrial contractions(fPACs) increased the risk of adverse cardiovascular outcomes, especially atrial fibrillation(AF), there is a substantial inconsistency between reports concerning the definition of fPAC. In this study, we aimed to investigate the relationship between fPAC and cardiovascular outcomes, especially AF. We further searched for a cutoff value of fPAC for prediction of AF. METHODS: We retrospectively analyzed the ambulatory 24-hr Holter monitoring records and 392 patients included. Frequent PAC was defined as more than 720 PAC/24 hr as used for frequent ventricular premature beats. Patients' baseline characteristics, echocardiographic variables and medical history were recorded. RESULTS: There were 189 patients with fPAC and 203 patients without fPAC. Patients with fPAC had more comorbidities in terms of hypertension, diabetes mellitus, coronary artery disease and congestive heart failure. CHA2DS2-VaSc was higher in patients with fPAC. Mean follow-up duration was 31 months, and the number of patients with new-onset AF during follow-up was significantly higher in fPAC group (22% vs. 5%, p < .001). fPAC was significantly and independently associated with new-onset AF and predicted AF with a cutoff value of 3,459 PAC/24 hr, and the risk of AF was 11-fold higher than those with <3,000 PAC/24 hr. In addition, an increased CHA2DS2-VaSc score was also associated with new-onset atrial fibrillation. CONCLUSION: In our study, we have demonstrated that fPAC is significantly associated with new-onset AF, and this association is the strongest among those patients who have more than 3,000 PAC in 24 hr.

The relationship between galectin-3 levels and fragmented QRS (fQRS) in patients with heart failure with reduced left ventricular ejection fraction.

BACKGROUND: Fragmented QRS (fQRS) complex is an electrocardiographic pattern which reflects myocardial scarring. We aimed to investigate the relationship between the presence of fragmented QRS (fQRS) on electrocardiogram (ECG) and plasma galectin-3 levels in patients with heart failure (HF) and severely decreased left ventricular ejection fraction (LVEF ≤ 35%). METHODS: We prospectively enrolled 125 symptomatic HF patients (NYHA class II-III) with severely reduced LVEF (≤35%). fQRS was identified in ECG. Galectin-3 and N-terminal pro-brain natriuretic peptide (NT-proBNP) levels were measured. Patients were divided into two groups based on the presence (n = 40) or absence (n = 85) of a fQRS on ECG. RESULTS: Majority of patients were male (87.70%), and mean age was 65.1 ± 11.6. Galectin-3 and NT-proBNP levels were found to be significantly higher in the fQRS (+) group compared with the fQRS (-) group (NT-proBNP 5,362 ± 701 pg/ml vs. 4,452 ± 698 pg/ml; p < 0.001, galectin-3 607 ± 89.8 pg/ml vs. 509.4 ± 63.5 pg/ml; p < 0.001). Multivariate analyses revealed galectin-3 and NT-proBNP levels are the presence of fQRS on ECG (p < 0.001 and p < 0.001, respectively). The area under the curve using the galectin-3 level for fQRS was 0.819. CONCLUSIONS: fQRS and serum galectin-3 levels are associated with myocardial fibrosis and are associated with poor prognosis in heart failure. In our study, a positive correlation was found between serum galectin-3 levels and fQRS on ECG.

Physical and cardiovascular performance in cases with acromegaly after regular short-term exercise.

OBJECTIVE: Impaired physical performance is a disturbing complication of acromegaly. We aimed to evaluate the role of regular exercise in amelioration of the impaired physical performance in acromegaly. METHODS: Patients with acromegaly were divided into two groups according to their participation in a prescheduled programme of exercise. Participants in the study group were exercised 3 days a week for 3 consecutive months. Exercise tolerance was evaluated by maximal oxygen consumption (VO2 max) and time (T) taken to complete the Bruce protocol, muscle flexibility by the sit and reach test (SRT) and muscle strength by the hand grip strength test (HGST). Concomitantly, anthropometric assessment was performed using body mass index (BMI), waist-to-hip ratio (WHR), skinfold measurements from 8 points, percentage body fat (PBF), fat mass (FM) and lean body mass (LBM). RESULTS: After 3 months of exercise, VO2 max and T were higher in cases that exercised than in cases that did not (P = 0.004 and P = 0.001). Over 3 months, within the exercise group, VO2 max and T of the Bruce protocol increased (P = 0.003 and P = 0.004) and heart rate during warming decreased (P = 0.04). SRT increased within the exercise group after 3 months (P = 0.004). HGSRT did not change significantly (right P = 0.06 and left P = 0.2). The sum of skinfolds, BMI, WHR and LBM remained stable over the study period (P = 0.1, P = 0.08, P = 0.3 and P = 0.09). PBF decreased slightly and FM decreased significantly over 3 months (P = 0.05 and P = 0.03). CONCLUSION: Even short-term exercise may improve impaired physical performance, muscle activity and disturbed body fat composition in acromegaly.

Long-Term Impact of Different Immunosuppressive Drugs on QT and PR Intervals in Renal Transplant Patients.

BACKGROUND: Sudden cardiac deaths due to arrhythmias are thought to be an important cause of mortality in patients with renal transplants. Exposure to immunosuppressive drugs may lead to QT or PR interval abnormalities which may consequently cause arrhythmias. Our study investigated the long term impact of four different immunosuppressive drugs on PR and corrected QT intervals (QTc) in renal transplant patients METHODS: The study population consisted of 98 kidney transplant recipients. Study patients were receiving immunosuppressive management with tacrolimus, cyclosporine A, everolimus or azathioprine according to the local protocols. QTc and PR intervals obtained from the most recent post-transplant electrocardiograms were compared with the pre-transplant intervals dated before the transplantation procedure. RESULTS: Post-transplant QTc intervals had prolonged significantly in comparison to the pre-transplant QTc intervals in all groups. However, there were no significant differences between the immunosuppressive agents with regard to post-transplant QTc interval prolongation (p > 0.05). There were no significant differences between the groups with regard to the pre and post-transplant PR interval changes (p > 0.05). CONCLUSIONS: QT interval prolongation, a marker of risk for arrhythmias and sudden death, is highly prevalent among kidney transplant patients receiving different classes of immunosuppressive drugs.

The relationship between aortic stiffness and serum hyaluronidase levels in patients with diabetes mellitus and hypertension.

The aim of this study was to investigate the association of serum hyaluronidase and nitric oxide (NO) levels with arterial stiffness in patients with hypertension (HT) and diabetes mellitus (DM). A total of 101 patients with diagnosis of DM and HT were enrolled in this study. The patients were divided into three groups as follows: only hypertensive (I), only diabetic (II) and both diabetic and hypertensive (III). Serum hyaluronidase levels were negatively correlated with aortic strain (AS) and aortic distensibility (AOD) in all groups, whereas a significant positive correlation was noted between serum hyaluronidase levels and aortic strain index (ASI) (all p-values < 0.05). There was a significant negative correlation between serum hyaluronidase and NO levels in all patients (p < 0.001). When the correlation between serum hyaluronidase and serum NO levels was investigated in the individual patient groups, a negative correlation was found in groups I, II and III (p = 0.017, p < 0.001 and p < 0.001, respectively). A significant relationship between plasma hyaluronidase level and parameters of aortic stiffness was found in patients with HT and/or DM. We suggest that the pathophysiological mechanisms responsible for the development of arterial stiffness in subjects with impaired endothelial function may involve pathological changes in the HA metabolism.

Significance and usefulness of narrow fragmented QRS complex on 12-lead electrocardiogram in acute ST-segment elevation myocardial infarction for prediction of early mortality and morbidity.

BACKGROUND: The presence of notched R or S waves without accompanying typical bundle branch blocks, or the existence of an additional wave like RSR' pattern in the original QRS complex (with a duration of <120 ms) has been defined as narrow QRS fragmentation. Persistence of the fQRS found on the admission electrocardiogram (ECG) in patients with acute ST segment elevation myocardial infarction (STEMI) will have prognostic significance in the short term. METHODS: The study was carried out using retrospectively collected data of 296 consecutive patients diagnosed as acute STEMI .fQRS group had fQRS both in admission and latest ECGs (n = 80, 27%), and non-fQRS group had no fQRS in last ECG (n = 216, 73%). Primary end points were in-hospital cardiovascular mortality, hemodynamic instability, and electrical instability. RESULTS: MI localization, symptom duration, reperfusion therapy (RPT) rate, RPT modality, rate of successful reperfusion did not differ. Mean ejection fraction was lower and all end points were more frequent in the fQRS group. Irrespective of the RPT modality and success of RPT, mortality rate was higher in patients with persistent fQRS. GRACE score >120 points (OR = 4.765), age >70 years (OR = 4.041), anterior MI localization (OR = 3.148), and presence of fQRS (OR = 2.484) were significant predictors of primary end points. fQRS increased the predictive ability of GRACE score >120 about two folds (OR = 7.305, P < 0.001). CONCLUSION: Persistent fQRS on ECG is associated with poor prognosis and there is a lack of expected mortality benefit of RPT, particularly that of fibrinolytic therapy, in STEMI patients with fQRS.

Evaluation of human immunodeficiency virus infection-related left ventricular systolic dysfunction by tissue Doppler strain echocardiography.

OBJECTIVE: Cardiovascular involvement causes significant morbidity and mortality among patients with human immunodeficiency virus (HIV) infection. Since the introduction of highly active antiretroviral treatment (HAART), subtle changes in left ventricular (LV) function, which may be clinically silent, have become more pronounced in HIV patients. Echocardiographic strain imaging (SI) may detect subclinical myocardial dysfunction at an earlier stage compared with conventional echocardiography. The aim of this study was to evaluate tissue Doppler-derived LV strain and strain rate (SR) along with conventional measures of LV function in asymptomatic, stable adult HIV patients on HAART. METHODS: Twenty-one patients with HIV infection (mean age: 37.8 ± 11.9 years, 11 males) who had no cardiovascular complaints and 27 healthy volunteers (mean age: 40.9 ± 5.8 years, 14 males) were enrolled. Traditional parameters including LV ejection fraction (EF) were measured along with tissue velocity imaging (TVI) and tissue Doppler SI parameters using transthoracic echocardiography. RESULTS: The mean duration of HIV infection was 30.8 ± 25.1 (3-120) months. The mean LVEF in HIV group was within normal limits but lower than controls (64.5% ± 10.2% vs. 72.2% ± 6.4%, P = 0.003). There were no differences in other major traditional measures, as well as TVI parameters between groups. LV systolic strain and SR parameters were impaired indicating subtle LV systolic dysfunction in HIV group. No difference in diastolic function was observed between groups. CONCLUSION: Left ventricular systolic strain parameters may be utilized to demonstrate subtle LV systolic dysfunction in asymptomatic HIV patients.

Current barriers and recommendations on the diagnosis of transthyretin amyloid cardiomyopathy: a Delphi study.

Objectives: This study has been conducted to investigate the non-invasive diagnostic journey of patients with a transthyretin amyloid cardiomyopathy (aTTR-CM) in Turkey, identify the challenges and uncertainties encountered on the path to diagnosis from the perspectives of expert physicians, and develop recommendations that can be applied in such cases. Methods: This study employed a three-round modified Delphi method and included 10 cardiologists and five nuclear medicine specialists. Two hematologists also shared their expert opinions on the survey results related to hematological tests during a final face-to-face discussion. A consensus was reached when 80% or more of the panel members marked the "agree/strongly agree" or "disagree/strongly disagree" option. Results: The panelists unanimously agreed that the aTTR-CM diagnosis could be established through scintigraphy (using either 99mTc-PYP, 99mTc-DPD, or 99mTc-HMPD) in a patient with suspected cardiac amyloidosis (CA) without a further investigation if AL amyloidosis is ruled out (by sFLC, SPIE and UPIE). In addition, scintigraphy imaging performed by SPECT or SPECT-CT should reveal a myocardial uptake of Grade ≥2 with a heart-to-contralateral (H/CL) ratio of ≥1.5. The cardiology panelists recommended using cardiovascular magnetic resonance (CMR) and a detailed echocardiographic scoring as a last resort before considering an endomyocardial biopsy in patients with suspected CA whose scintigraphy results were discordant/inconclusive or negative but still carried a high clinical suspicion of aTTR-CM. Conclusion: The diagnostic approach for aTTR-CM should be customized based on the availability of diagnostic tools/methods in each expert clinic to achieve a timely and definitive diagnosis.

Do trace elements play a role in coronary artery calcification in hemodialysis patients?

PURPOSE: Abnormalities of trace elements have previously been linked to inflammatory processes in hemodialysis (HD) patients. We aimed to establish the trace element status of maintenance HD patients, to investigate the relationship between coronary artery calcification scores (CACs) and whole blood levels of trace elements. METHODS: Patients undergoing HD in three times a week for > 6 months and age-and sex-matched controls were included from October 2015 to June 2016. Data were collected from patient files. All subjects' whole blood levels of trace elements were measured by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). CACs for patients were assessed by multi-detector computed tomography. RESULTS: The 35 patients (male, 60%) with a mean age of 45.7 ± 10.4 years and 35 controls were included. HD patients showed significantly lower levels of selenium and uranium and higher cadmium (Cd), cobalt, lithium, manganese, nickel, lead, platinum, tin, strontium, and thallium levels compared to controls. Coronary artery calcification (CAC) was present in 21 patients (60%), and median CACs were 14.2 (IQR 0-149). Patients with CACs > median were significantly older, had a higher prevalence of hypertension and lower ALP levels than patients with CACs ≤ median. No significant differences in whole blood levels of trace elements were found between patients with CACs > median and patients with CACs ≤ median. A near significance was noted in median whole blood levels of Cd between these groups (P = 0.096). According to multivariate analysis, age was the only independent determinant for CAC development. CONCLUSION: Age is independently associated with coronary vascular calcification. High Cd levels might play a role in CAC development in HD patients.

Non-dominant right coronary artery (RCA) is associated with suspected inferior ischemia on SPECT in patients without significant coronary artery disease (CAD).

OBJECTIVE: There is a huge uncertainty in the medical community regarding the significance of non-dominant right coronary artery (RCA) in patients with inferior wall ischemia on myocardial perfusion single-photon emission computed tomography (SPECT). The purpose of this study is to determine the effect of non-dominant RCA on myocardial perfusion SPECT (MPS) with respect to the misleading detection of ischemia in the inferior wall of the myocardium. METHODS: This is a retrospective study of 155 patients, who had undergone elective coronary angiography owing to an indication of inferior wall ischemia by MPS between 2012 and 2017. Patients were divided into two groups based on the coronary dominance: group 1 (n = 107), if RCA is the dominant artery, and group 2 (n = 48), if there are dominance of left artery and codominance of both arteries. Obstructive CAD was diagnosed in the case of stenosis that had severity greater than 50%. The positive predictive value (PPV), which was calculated as per the correlation between the inferior wall ischemia in MPS and obstruction level in RCA, was compared in both groups. RESULTS: Majority of patients were male (109, 70%) and the mean age was 59.5 ± 10.2. There were 45 patients with obstructive RCA disease (PPV: 42%) among 107 patients in group 1, whereas there were only 8 patients with obstructive coronary artery disease (CAD) in RCA among 48 patients in group 2, (PPV: 16% and p = 0.004). CONCLUSIONS: The results demonstrated that non-dominant RCA is associated with false-positive detection of inferior wall ischemia via MPS.

Intracardiac electrogram characteristics of intramural outflow tract ventricular arrhythmias.

BACKGROUND: Annotation of earliest depolarization which depends on maximum dV/dt of unipolar-electrograms and unipolar QS morphology identify site of origin for ventricular premature contractions (VPC). However, identification of unipolar QS morphology has limitations due to low spatial resolution. This study aims to compare electrogram characteristics at successful ablation site in patients with outflow tract (OT) VPC. METHODS: Local activation time (LAT), duration, and voltage data of each bipolar- and unipolar-electrogram at the successful ablation sites from the right ventricle OT (RVOT) and the left ventricle OT (LVOT) cases were analyzed. RESULTS: Forty-four of 60 (73%) of patients were ablated from RVOT and in 16/60 (27%) required ablation from both sides. All patients had acute VPC suppression. Bipolar-electrogram-QRS onset was earlier (36.4 ± 14.5 ms vs 26.3 ± 7.4 ms, p = 0.01), duration of bipolar-electrogram was shorter (56.9 ± 18.9 ms vs 78.9 ± 21.8 ms, p = 0.002), and bi-voltage amplitude was higher (3.2 ± 2.3 mV vs 1.4 ± 1.1 mV, p = 0.07) for patients with RVOT-only ablation. Mean bipolar-unipolar-electrogram difference was 4.4 ± 4.5 ms in the RVOT group vs 12.8 ± 4.9 ms in RVOT + LVOT group (p < 0.001). Unipolar QS morphology was recorded in 3.0 ± 3.9 vs 3.6 ± 1.8 cm2 in RVOT and RVOT + LVOT group, respectively (p = 0.41). Unipolar-electrogram revealed W pattern in 3/44 of RVOT vs 5/16 of RVOT + LVOT group, respectively (p = 0.01). In 18/60 (30%) of patients, unipolar QS was not identified at successful ablation site. CONCLUSION: QS in unipolar-electrogram was not a perfect predictor for successful ablation sites. Analysis of bipolar voltage amplitude and duration with bipolar-unipolar-electrogram time difference may identify presence of a deeper source.

Diagnostic accuracy of Apple Watch Series 6 recorded single-lead ECGs for identifying supraventricular tachyarrhythmias: a comparative analysis with invasive electrophysiological study.

BACKGROUND: The advancements in wearable technology have made the detection of arrhythmias more accessible. While smartwatches are commonly used to detect patients with atrial fibrillation, their effectiveness in the differential diagnosis of supraventricular tachycardias (SVT) lacks consensus. METHODS: A study was conducted on 47 patients with documented SVTs on a 12-lead ECG. All patients in the cohort underwent electrophysiology study with induction of SVT. A 6th generation Apple Watch was used to record ECG tracings during baseline sinus rhythm and during induced SVT. Cardiology residents and attending cardiologists evaluated these recordings to diagnose the differential diagnosis of SVT. RESULTS: The evaluation revealed 27 cases of typical atrioventricular nodal reentrant tachycardia (AVNRT), 11 cases of atrioventricular reentrant tachycardia (AVRT), and 9 cases of atrial tachycardia/atrial flutter (AT/AFL) among the induced tachycardias. Attending physicians achieved an accuracy of 66.0 to 76.6%, and residents demonstrated accuracy rates between 68.1 and 74.5%. Interrater reliability was assessed using Fleiss's Kappa method, resulting in a moderate level of agreement between residents (Kappa = 0.465, p < 0.001, 95% CI 0.30-0.63) and attendings (Kappa = 0.519, p < 0.001, 95% CI 0.35-0.68). The overall Kappa value was 0.417 (p < 0.001, 95% CI 0.34-0.49). CONCLUSIONS: Smartwatch recordings demonstrate moderate feasibility in diagnosing SVT when following a pre-specified algorithm. However, this diagnostic performance was lower than the accuracy obtained from 12-lead ECG tracings when blinded to procedure outcomes.