Genetic Susceptibility to Arrhythmia Phenotypes in a Middle Eastern Cohort of 14,259 Whole-Genome Sequenced Individuals.

Background: The current study explores the genetic underpinnings of cardiac arrhythmia phenotypes within Middle Eastern populations, which are under-represented in genomic medicine research. Methods: Whole-genome sequencing data from 14,259 individuals from the Qatar Biobank were used and contained 47.8% of Arab ancestry, 18.4% of South Asian ancestry, and 4.6% of African ancestry. The frequency of rare functional variants within a set of 410 candidate genes for cardiac arrhythmias was assessed. Polygenic risk score (PRS) performance for atrial fibrillation (AF) prediction was evaluated. Results: This study identified 1196 rare functional variants, including 162 previously linked to arrhythmia phenotypes, with varying frequencies across Arab, South Asian, and African ancestries. Of these, 137 variants met the pathogenic or likely pathogenic (P/LP) criteria according to ACMG guidelines. Of these, 91 were in ACMG actionable genes and were present in 1030 individuals (~7%). Ten P/LP variants showed significant associations with atrial fibrillation p < 2.4 × 10-10. Five out of ten existing PRSs were significantly associated with AF (e.g., PGS000727, p = 0.03, OR = 1.43 [1.03, 1.97]). Conclusions: Our study is the largest to study the genetic predisposition to arrhythmia phenotypes in the Middle East using whole-genome sequence data. It underscores the importance of including diverse populations in genomic investigations to elucidate the genetic landscape of cardiac arrhythmias and mitigate health disparities in genomic medicine.

Correlations between Resting Electrocardiogram Findings and Disease Profiles: Insights from the Qatar Biobank Cohort.

BACKGROUND: Resting electrocardiogram (ECG) is a valuable non-invasive diagnostic tool used in clinical medicine to assess the electrical activity of the heart while the patient is resting. Abnormalities in ECG may be associated with clinical biomarkers and can predict early stages of diseases. In this study, we evaluated the association between ECG traits, clinical biomarkers, and diseases and developed risk scores to predict the risk of developing coronary artery disease (CAD) in the Qatar Biobank. METHODS: This study used 12-lead ECG data from 13,827 participants. The ECG traits used for association analysis were RR, PR, QRS, QTc, PW, and JT. Association analysis using regression models was conducted between ECG variables and serum electrolytes, sugars, lipids, blood pressure (BP), blood and inflammatory biomarkers, and diseases (e.g., type 2 diabetes, CAD, and stroke). ECG-based and clinical risk scores were developed, and their performance was assessed to predict CAD. Classical regression and machine-learning models were used for risk score development. RESULTS: Significant associations were observed with ECG traits. RR showed the largest number of associations: e.g., positive associations with bicarbonate, chloride, HDL-C, and monocytes, and negative associations with glucose, insulin, neutrophil, calcium, and risk of T2D. QRS was positively associated with phosphorus, bicarbonate, and risk of CAD. Elevated QTc was observed in CAD patients, whereas decreased QTc was correlated with decreased levels of calcium and potassium. Risk scores developed using regression models were outperformed by machine-learning models. The area under the receiver operating curve reached 0.84 using a machine-learning model that contains ECG traits, sugars, lipids, serum electrolytes, and cardiovascular disease risk factors. The odds ratio for the top decile of CAD risk score compared to the remaining deciles was 13.99. CONCLUSIONS: ECG abnormalities were associated with serum electrolytes, sugars, lipids, and blood and inflammatory biomarkers. These abnormalities were also observed in T2D and CAD patients. Risk scores showed great predictive performance in predicting CAD.

Morbidity and mortality of acute heart failure patients stratified by mitral regurgitation in the Arabian Gulf: Observations from the Gulf acute heart failure registry (Gulf CARE).

This study aimed to evaluate the clinical outcomes of patients with acute heart failure (AHF) stratified by mitral regurgitation (MR) in the Arabian Gulf. Patients from the Gulf CARE registry were identified from 47 hospitals in seven Arabian Gulf countries (Yemen, Oman, Kuwait, Qatar, Bahrain, the United Arab Emirates, and Saudi Arabia) from February to November 2012. The cohort was stratified into two groups based on the presence of MR. Univariable and multivariable statistical analyses were performed. The population cohort included 5005 consecutive patients presenting with AHF, of whom 1491 (29.8 %) had concomitant MR. The mean age of patients with AHF and concomitant MR was 59.2 ± 14.9 years, and 63.1 % (n = 2886) were male. A total of 58.6 % (n = 2683) had heart failure (HF) with reduced ejection fraction (EF) (HFrEF), 21.0 % (n = 961) had HF with mildly reduced EF (HFmrEF), and 20.4 % (n = 932) had HF with preserved EF (HFpEF). Patients with MR had a lower haemoglobin (Hb) level (12.4 vs. 12.7 g/dL; p < 0.001), and a higher prevalence of left atrial enlargement (80.2 % vs. 55.1 %; p < 0.001), cardiogenic shock (9.7 % vs. 7.3 %; p = 0.006) and atrial fibrillation (7.6 % vs. 5.6 %; p = 0.006), and HFrEF (71.0 % vs. 52.6 %; P < 0.001). Multivariable analysis demonstrated that MR was independently associated with increased all-cause mortality at 1-year and 3-month HF rehospitalization [1-year all-cause mortality, adjusted odds ratio (aOR), 1.40; 95 % confidence interval (Cl): 1.13-1.74; p = 0.002; 3-month HF rehospitalization, aOR, 1.26; 95 % Cl: 1.06-1.49; p = 0.009]. In an Arabian Gulf cohort with AHF, concomitant MR was associated with an increased risk of 1-year mortality and 3-months HF rehospitalization.

Patterns and Outcomes of Obesity Using Body Mass Index in Patients Hospitalized with Acute Cardiovascular Disorders: A Retrospective Analysis of 7284 Patients in a Middle Eastern Country.

BACKGROUND: We aimed to study the presentation and in-hospital outcomes of obese patients hospitalized for cardiovascular diseases (CVDs) in a Middle Eastern country. METHODS: This retrospective study included patients admitted to the Heart Hospital between 2015 and 2020. Patients were divided according to their body mass index (BMI): Group I (BMI 18.5-24.9), Group II (BMI 25-29.9), and Group III (BMI ≥ 30), by applying one-way ANOVAs and chi-square tests. The obese group (BMI ≥ 30) was graded and compared (Grade I (BMI 30-34.9), Grade II (BMI 35-39.9), and Grade III (BMI ≥ 40)). RESULTS: There were 7284 patients admitted with CVDs (Group I (29%), Group II (37%), and Group III (34%)). The mean age was higher in Group III than Groups I and II (p < 0.001). Male sex was predominant in all groups except for morbid obesity (Grade III), in which females predominated. Diabetes mellitus (DM), hypertension, and dyslipidemia were more common in Group III. Chest pain was more common in Group II, while shortness of breath was more evident in Group III (p < 0.001). Group II had more ST-elevation myocardial infarction (STEMI), followed by Group I (p < 0.001). Atrial fibrillation (AF) was observed more frequently in Group III (p < 0.001). Congestive heart failure (CHF) was common in Group III (19%) (p < 0.001). In the subanalysis, (Grade I (62%), Grade II (22.5%), and Grade III (15.5%)), Grade I had more STEMI, whereas AF and CHF were higher in Grade III (p < 0.001). Percutaneous Coronary Intervention was performed less frequently in Grade III (p < 0.001). In-hospital mortality was higher in Grade III (17.1%), followed by Grades II (11.2%) and I (9.3%) (p < 0.001). CONCLUSIONS: In this study, one third of the hospitalized CVS patients were obese. AF and CHF with preserved EF were the most common cardiovascular presentations in obese patients. In patients with CVDs, obesity was associated with higher rates of comorbidities and in-hospital mortality. However, obesity measured by BMI alone was not an independent predictor of mortality in obese cardiac patients.

Predictors of 30-Day Re-admission in Cardiac Patients at Heart Hospital, Qatar.

Background: Cardiovascular disease patients are more likely to be readmitted within 30 days of being discharged alive. This causes an enormous burden on health-care systems in terms of poor care of patients and misutilization of resources. Aims and Objective: This study aims to find out the risk factors associated with 30-day readmission in cardiac patients at Heart Hospital, Qatar. Methods: A total of 10,550 cardiac patients who were discharged alive within 30 days at the heart hospital in Doha, Qatar, from January 2015 and December 2019 were analyzed. The bootstrap method, an internal validation statistical technique, was applied to present representative estimates for the population. Results: Out of the 10,550 cardiac patients, there were 8418 (79.8%) index admissions and 2132 (20.2%) re-admitted at least once within 30 days after the index admission. The re-admissions group was older than the index admission group (65.6 ± 13.2 vs. 56.0 ± 13.5, P = 0.001). Multinomial regression analysis showed that females were 30% more likely to be re-admitted than males (adjusted odds ratio [aOR] 1.30, 95% confidence interval [CI]: 1.11-1.50, P = 0.001). Diabetes (aOR 1.36, 95% CI: 1.20-1.53, P = 0.001), chronic renal failure (aOR 1.93, 95% CI: 1.66-2.24, P = 0.001), previous MI (aOR 3.22, 95% CI: 2.85-3.64, P = 0.001), atrial fibrillation (aOR 2.17, 95% C.I. : 1.10-2.67, P = 0.01), cardiomyopathy (aOR 1.72, 95% CI 1.47-2.02, P = 0.001), and chronic heart failure (aOR 1.56, 95% C.I.: 1.33-1.82, P = 0.001) were also independent predictors for re-admission in the regression model. C-statistics showed these variables could predict 82% accurately hospital readmissions within 30 days after being discharged alive. Conclusion: The model was more than 80% accurate in predicting 30-day readmission after being discharged alive. The presence of five or more risk factors was found to be crucial for readmissions within 30 days. The study may help design interventions that may result in better outcomes with fewer resources in the population.

Evaluation of mortality attributable to SARS-CoV-2 vaccine administration using national level data from Qatar.

Accurate determination of mortality attributable to SARS-CoV-2 vaccination is critical in allaying concerns about their safety. We reviewed every death in Qatar that occurred within 30 days of any SARS-CoV-2 vaccine administration between January 1, 2021 and June 12, 2022. Probability of association with SARS-CoV-2 vaccination was determined by four independent trained reviewers using a modified WHO algorithm. Among 6,928,359 doses administered, 138 deaths occurred within 30 days of vaccination; eight had a high probability (1.15/1,000,000 doses), 15 had intermediate probability (2.38/1,000,000 doses), and 112 had low probability or no association with vaccination. The death rate among those with high probability of relationship to SARS-CoV-2 vaccination was 0.34/100,000 unique vaccine recipients, while death rate among those with either high or intermediate probability of relationship to SARS-CoV-2 vaccination was 0.98/100,000 unique vaccine recipients. In conclusion, deaths attributable to SARS-CoV-2 vaccination are extremely rare and lower than the overall crude mortality rate in Qatar.

Smoking in Acute Myocardial Infarction Patients: Observations from a Registry Heart Hospital, Qatar.

Introduction: Studies from the US and Europe showed a decline in smoking among patients with acute myocardial infarction (AMI), but limited data are available from the Middle East. In this study, we describe the temporal trend in the prevalence, associated risk factors, and outcomes of smoking among patients with AMI in Qatar. Materials and Methods: A total of 27,648 AMI patients were analyzed from the cardiology registry at Heart Hospital, Doha, Qatar. This spans from January 1991 to May 2022. Results: Of the total, 13,562 patients (49.1%, 95% confidence interval [CI]: 48%-50%) were smokers, with a clear majority of males (98.5%). Smoking habit was found to decrease in AMI patients with increasing age (age 51-60 years, adjusted odds ratio [OR]: 0.71, 95% CI: 0.67-0.76, P = 0.001, and age ≥61 years, adjusted OR: 0.45, 95% CI: 0.42-0.48, P = 0.001, in comparison to age ≤50 years). Smoking was associated with a lower risk of inhospital mortality (adjusted OR: 0.61, 95% CI: 0.54-0.70, P = 0.001), but triglyceride, obesity, and old myocardial infarction risk factors were associated with a higher risk. A decreasing trend in current smoking habits in each quantile of the 1996-2000 year (adjusted OR: 0.82, 95% CI: 0.71-0.93, P = 0.001), 2001-2005 year (adjusted OR: 0.70, 95% CI: 0.62-0.80, P = 0.001), 2006-2010 year (adjusted OR: 0.75, 95% CI: 0.67-0.84, P = 0.001), 2011-2015 year (adjusted OR: 0.48, 95% CI: 0.42-0.54, P = 0.001), 2016-2020 year (adjusted OR: 0.48, 95% CI: 0.43-0.54, P = 0.001), and ≥2021 year (adjusted OR: 0.46, 95% CI: 0.40-0.53, P = 0.001) was observed in comparison to the quantile 1991-1995 year. Similar results were also observed in the young population (age ≤50 years) including the non-Qataris, who had 25% more smokers in comparison to Qatari nationals. Conclusion: Smoking trended down significantly; however, it remained prevalent in 50% of patients among AMI patients. Smokers were younger, with fewer traditional risk factors, and had lower inhospital mortality.

Atrioventricular Conduction Disorders as a Complication of Inferior ST-Elevation Myocardial Infarction in Patients with COVID-19 Infection.

This case series demonstrates how COVID-19 infection might affect the heart in the context of acute myocardial infarction. Atrioventricular (AV) block might appear as one of the significant cardiac complications of acute MI in patients who tested COVID-19 PCR positive regardless of the presence of CVOID-19 infection symptoms. In our series, conduction disorders as a complication of acute inferior STEMI are more common in patients who tested positive for the COVID-19 infection. 11 patients out of 18 inferior STEMI patients who have tested positive for the COVID-19 infection have atrioventricular block disorders.

The "obesity paradox" in patients with atrial fibrillation: Insights from the Gulf SAFE registry.

Background: The prognostic impact of obesity on patients with atrial fibrillation (AF) remains under-evaluated and controversial. Methods: Patients with AF from the Gulf Survey of Atrial Fibrillation Events (Gulf SAFE) registry were included, who were recruited from six countries in the Middle East Gulf region and followed for 12 months. A multivariable model was established to investigate the association of obesity with clinical outcomes, including stroke or systemic embolism (SE), bleeding, admission for heart failure (HF) or AF, all-cause mortality, and a composite outcome. Restricted cubic splines were depicted to illustrate the relationship between body mass index (BMI) and outcomes. Sensitivity analysis was also conducted. Results: A total of 1,804 patients with AF and recorded BMI entered the final analysis (mean age 56.2 ± 16.1 years, 47.0% female); 559 (31.0%) were obese (BMI over 30 kg/m2). In multivariable analysis, obesity was associated with reduced risks of stroke/systematic embolism [adjusted odds ratio (aOR) 0.40, 95% confidence interval (CI), 0.18-0.89], bleeding [aOR 0.44, 95%CI, 0.26-0.74], HF admission (aOR 0.61, 95%CI, 0.41-0.90) and the composite outcome (aOR 0.65, 95%CI, 0.50-0.84). As a continuous variable, higher BMI was associated with lower risks for stroke/SE, bleeding, HF admission, all-cause mortality, and the composite outcome as demonstrated by the accumulated incidence of events and restricted cubic splines. This "protective effect" of obesity was more prominent in some subgroups of patients. Conclusion: Among patients with AF, obesity and higher BMI were associated with a more favorable prognosis in the Gulf SAFE registry. The underlying mechanisms for this obesity "paradox" merit further exploration.

An Ectopic Primary Pacemaker in Association with Isolated Persistent Left Superior Vena Cava.

We are reporting a case of a young Nepalese man, who was not known to have any past medical history, and who presented with palpitations. An electrocardiogram showed negative P-waves atrial rhythm in II, III, arteriovenous fistula, and V3-V6 with a variable block at 90-130 bpm. No positive "normal" P-waves were demonstrated in any tracing. He was found to have a congenital absence of the right superior vena cava (RSVC) along with persistent left superior vena cava (PLSVC) a condition also called isolated PLSVC (IPLSC). He underwent a treadmill stress test for further evaluation which showed a normal chronotropic response and the same persistent negative P-waves morphology. An invasive electroanatomical and activation mapping showed an absence of RSVC, the earliest atrial activation site in the anterior side of the inferior vena cava (IVC), and the absence of normal (positive) P-waves/normal sinus node (SN) activation. Considering all the available clinical data together, we believe that the patient was living with an ectopic pacemaker node that acts as a primary node and originated in the IVC/right atrium instead of the normal expected SN position. Given the high risk of complete sinoatrial nodal block in case of radiofrequency ablation, the patient was kept on medical treatment with a beta-blocker which was effective in controlling his symptoms and atrial arrhythmia.

Gender Association with Incidence, Clinical Profile, and Outcome of Out-of-Hospital Cardiac Arrest: A Middle East Perspective.

Background: Out-of-hospital cardiac arrest (OHCA) is a leading cause of death worldwide. However, there is limited information on the outcome of the OHCA in the Middle East population, and limited studies have been carried out in the Arab Gulf countries. Hence, we aim to study the incidence and rate of survival in the OHCA setting and to assess the impact of gender on the clinical outcome following OHCA. Methods: Retrospective analysis of a prospective registry of all eligible, consecutive, and nontraumatic adult patients who successfully resuscitated (return of spontaneous circulation) from "Cardiac Arrest" occurring outside the hospital, Hospitalized in Doha, Qatar from January 1991 to June 2010. Results: A total of 41,453 consecutive patients were admitted during the study, of whom 987 (2.4%) had a diagnosis of OHCA. Among them, 269 (27.3%) were women and 718 (72.7%) were men. Although the mortality rate was higher in females than in males (65.4% vs. 57.7%, P = 0.03), the logistic regression analysis did not show gender as an independent predictor of death in this clinical setting. Conclusion: In this sample of the state population, women who have OHCAs had a lower rate of survival, but gender was not an independent predictor of mortality following OHCA.

Chronic reduction of store operated Ca2+ entry is viable therapeutically but is associated with cardiovascular complications.

Loss of function mutations in store-operated Ca2+ entry (SOCE) are associated with severe paediatric disorders in humans, including combined immunodeficiency, anaemia, thrombocytopenia, anhidrosis and muscle hypotonia. Given its central role in immune cell activation, SOCE has been a therapeutic target for autoimmune and inflammatory diseases. Treatment for such chronic diseases would require prolonged SOCE inhibition. It is, however, unclear whether chronic SOCE inhibition is viable therapeutically. Here we address this issue using a novel genetic mouse model (SOCE hypomorph) with deficient SOCE, nuclear factor of activated T cells activation, and T cell cytokine production. SOCE hypomorph mice develop and reproduce normally and do not display muscle weakness or overt anhidrosis. They do, however, develop cardiovascular complications, including hypertension and tachycardia, which we show are due to increased sympathetic autonomic nervous system activity and not cardiac or vascular smooth muscle autonomous defects. These results assert that chronic SOCE inhibition is viable therapeutically if the cardiovascular complications can be managed effectively clinically. They further establish the SOCE hypomorph line as a genetic model to define the therapeutic window of SOCE inhibition and dissect toxicities associated with chronic SOCE inhibition in a tissue-specific fashion. KEY POINTS: A floxed stromal interaction molecule 1 (STIM1) hypomorph mouse model was generated with significant reduction in Ca2+ influx through store-operated Ca2+ entry (SOCE), resulting in defective nuclear translocation of nuclear factor of activated T cells, cytokine production and inflammatory response. The hypomorph mice are viable and fertile, with no overt defects. Decreased SOCE in the hypomorph mice is due to poor translocation of the mutant STIM1 to endoplasmic reticulum-plasma membrane contact sites resulting in fewer STIM1 puncta. Hypomorph mice have similar susceptibility to controls to develop diabetes but exhibit tachycardia and hypertension. The hypertension is not due to increased vascular smooth muscle contractility or vascular remodelling. The tachycardia is not due to heart-specific defects but rather seems to be due to increased circulating catecholamines in the hypomorph. Therefore, long term SOCE inhibition is viable if the cardiovascular defects can be managed clinically.

Symptom Status, Clinical Subtypes, and Prognosis in Patients With Atrial Fibrillation from the Middle East Region (from the Gulf-SAFE Registry).

Atrial fibrillation (AF) is often asymptomatic. The prognosis of asymptomatic AF is at least similar or worse than symptomatic AF, but there are no such data from Middle East patients with AF. The Gulf-SAFE (Gulf Survey of Atrial Fibrillation Events) registry is a multicenter prospective survey of patients presenting with AF to participate medical institutions in 6 countries in the Gulf region. We investigated the prognostic outcomes of patients with asymptomatic AF in relation to clinical subtypes. A total of 2043 patients with AF were included; 541 were identified as having asymptomatic AF (26.5%) who tended to be older, with higher prevalences of hypertension, heart failure, coronary artery disease, diabetes, stroke, renal dysfunction, chronic obstructive pulmonary disease, and had higher Congestive heart failure, Hypertension, Age ≥75, Stroke (2 points), Congestive heart failure, Hypertension, Age ≥75 (2 points), Diabetes, Stroke (2 points), Vascular disease, Age 65-74, Sex category (CHA2DS2-VASc), and Hypertension, Age ≥65, Stroke, Bleeding history, liable INR, Elderly, Drug or alcohol use (HAS-BLED) scores (all p <0.05). After multivariable adjustment, asymptomatic AF was associated with higher risks of stroke/systematic embolism (SE) (adjusted odds ratio [aOR] 2.18, 95% confidence interval [CI] 1.10 to 4.34), all-cause mortality (aOR 2.85, 95% CI 1.90 to 4.28), and the composite outcome of stroke/SE, bleeding, and all-cause mortality (aOR 1.74, 95% CI 1.26 to 2.41). Patients with asymptomatic AF had fewer admissions for AF (aOR 0.53, 95% CI 0.32 to 0.83) and heart failure (aOR 0.58, 95% CI 0.38 to 0.86). The increased risk of stroke/SE in asymptomatic AF was more prominent among paroxysmal AF subtype (p for interaction = 0.028). In conclusion, in the Gulf-SAFE registry, patients with asymptomatic AF represent a nonbenign entity with worse outcomes compared with symptomatic AF. In paroxysmal AF, the higher risks of events were more prominent. The absence of "warning signs" and lack of timely admission in asymptomatic AF may be major reasons for the unfavorable prognosis.

A Comparative Study of Safety Outcomes of Sodium Glucose Cotransporter-2 Inhibitors and Loop Diuretics Among Diabetic Patients Using Real-world Data.

Sodium glucose cotransporter-2 (SGLT2) inhibitors and loop diuretics can cause volume depletion. However, the long-term safety of the concurrent use of both agents has not been widely evaluated. We conducted a retrospective observational cohort study to evaluate the safety of SGLT2 inhibitors with loop diuretics vs SGLT2 inhibitors alone among diabetic patients. The primary endpoint was a composite of volume-depletion adverse events at 1 month and 12 months. Of the 400 patients included, 98 received SGLT2 inhibitors with a loop diuretic and 302 received SGLT2 inhibitors alone. The concurrent use of SGLT2 inhibitors and loop diuretics was tolerated at 1 month; however, it resulted in a significant increase in volume-depletion events at 12 months (10.2% vs 1.7%; aHR = 7.03, 95% CI (1.80-27.37), P-value = 0.005). In conclusion, the long-term concurrent use of SGLT2 inhibitors and loop diuretics increases the risk of volume depletion, warranting frequent monitoring.

Rapid Exclusion of COVID Infection With the Artificial Intelligence Electrocardiogram.

OBJECTIVE: To rapidly exclude severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection using artificial intelligence applied to the electrocardiogram (ECG). METHODS: A global, volunteer consortium from 4 continents identified patients with ECGs obtained around the time of polymerase chain reaction-confirmed COVID-19 diagnosis and age- and sex-matched controls from the same sites. Clinical characteristics, polymerase chain reaction results, and raw electrocardiographic data were collected. A convolutional neural network was trained using 26,153 ECGs (33.2% COVID positive), validated with 3826 ECGs (33.3% positive), and tested on 7870 ECGs not included in other sets (32.7% positive). Performance under different prevalence values was tested by adding control ECGs from a single high-volume site. RESULTS: The area under the curve for detection of acute COVID-19 infection in the test group was 0.767 (95% CI, 0.756 to 0.778; sensitivity, 98%; specificity, 10%; positive predictive value, 37%; negative predictive value, 91%). To more accurately reflect a real-world population, 50,905 normal controls were added to adjust the COVID prevalence to approximately 5% (2657/58,555), resulting in an area under the curve of 0.780 (95% CI, 0.771 to 0.790) with a specificity of 12.1% and a negative predictive value of 99.2%. CONCLUSION: Infection with SARS-CoV-2 results in electrocardiographic changes that permit the artificial intelligence-enhanced ECG to be used as a rapid screening test with a high negative predictive value (99.2%). This may permit the development of electrocardiography-based tools to rapidly screen individuals for pandemic control.

Atrial fibrillation catheter ablation complications in obese and diabetic patients: Insights from the US Nationwide Inpatient Sample 2005-2013.

BACKGROUND: Obesity and diabetes are risk factors for atrial fibrillation (AF) incidence and recurrence after catheter ablation. However, their impact on post-ablation complications in real-world practice is unknown. OBJECTIVES: We examine annual trends in AF ablations and procedural outcomes in obese and diabetic patients in the US and whether obesity and diabetes are independently associated with adverse outcomes. METHODS: Using the Nationwide Inpatient Sample (2005-2013), we identified obese and diabetic patients admitted for AF ablation. Common complications were identified using ICD-9-CM codes. The primary outcome included the composite of any in-hospital complication or death. Annual trends of the primary outcome, length-of-stay (LOS) and total-inflation adjusted hospital charges were examined. Multivariate analyses studied the association of obesity and diabetes with outcomes. RESULTS: An estimated 106 462 AF ablations were performed in the US from 2005 to 2013. Annual trends revealed a gradual increase in ablations performed in obese and diabetic patients and in complication rates. The overall rate of the primary outcome in obese was 11.7% versus 8.2% in non-obese and 10.7% in diabetic versus 8.2% in non-diabetic patients (p < .001). CONCLUSIONS: Obesity was independently associated with increased complications (adjusted OR, 95% CI:1.39, 1.20-1.62), longer LOS (1.36, 1.23-1.49), and higher charges (1.16, 1.12-1.19). Diabetes was only associated with longer LOS (1.27, 1.16-1.38). Obesity, but not diabetes, in patients undergoing AF ablation is an independent risk factor for immediate post-ablation complications and higher costs. Future studies should investigate whether weight loss prior to ablation reduces complications and costs.

Exercise Ventricular Rates, Cardiopulmonary Exercise Performance, and Mortality in Patients With Heart Failure With Atrial Fibrillation.

BACKGROUND: In heart failure (HF) with sinus rhythm, resting and exercise heart rates correlate with exercise capacity and mortality. However, in HF with atrial fibrillation (AF), this correlation is unknown. Our aim is to investigate the association of resting and exercise ventricular rates (VRs) with exercise capacity and mortality in HF with AF. METHODS: We identified 903 patients with HF and AF referred for cardiopulmonary stress testing. AF was defined as history of AF and AF during cardiopulmonary stress testing. We constructed multivariable models to evaluate the association of resting VR, peak exercise VR, VR reserve (peak VR-resting VR), and chronotropic index with (1) peak oxygen consumption (PVO2) ≤18 mL/kg per minute, (2) continuous PVO2, and (3) 10-year all-cause mortality. RESULTS: Median (25th-75th percentile) age was 60 (52-67) years, left ventricular ejection fraction was 25 (15-50)%, and 76.1% were males. Patients with lower (quartile 1) compared with higher (quartile 4) peak VR, VR reserve, and chronotropic index were more likely to have PVO2 ≤18 mL/kg per min (adjusted odds ratio [95% CI]: 14.92 [8.07-27.58], 24.60 [12.36-48.98], and 22.31 [11.24-44.27], respectively), and higher all-cause mortality (adjusted hazard ratio [95% CI]: 2.56 [1.62-4.04], 2.29 [1.47-3.59], and 2.30 [1.51-3.49], respectively). For every 10 beats per minute increase in VR reserve, PVO2 increased by 1.05 mL/kg per minute (B-coefficient [95% CI]: 1.05 [0.94-1.15]) and mortality decreased by 12% (adjusted hazard ratio [95% CI]: 0.88 [0.83-0.94]). Resting VR was associated with PVO2 (B-coefficient [95% CI]: -0.46 [-0.70 to -0.23]) but not mortality (adjusted hazard ratio [95% CI]: 0.97 [0.88-1.06]). CONCLUSIONS: In patients with HF and AF, higher resting VR and lower peak exercise VR, VR reserve, and chronotropic index were all associated with worse peak exercise capacity, but only lower exercise VR parameters were associated with higher mortality. Dedicated studies are needed to gauge whether modulating exercise VR enhances exercise performance and outcomes.

The Role of Coronary Computed Tomography Angiography in Evaluation of High Troponin Patients with Narrow-Complex Supraventricular Tachycardia.

Aim: The aim of this study was to investigate the relation of high-sensitive cardiac troponin T (hs-cTnT) elevation with characteristics of supraventricular tachycardia (SVT) episode (duration and maximum heart rate) and coronary computed tomography angiography (CCTA) findings in patients with SVT who presented to the emergency room with palpitation. Methods: This retrospective, single-center, noninvasive study included all patients aged between 18 years and 65 years who presented to the emergency department due to narrow-complex SVT and underwent CCTA to rule out coronary artery disease (CAD) due to elevation of hs-cTnT and reverted back to sinus rhythm after intravenous adenosine. The first, second, and the maximum hs-cTnT levels were obtained from the database. The patients were classified into normal coronaries, nonobstructive CAD, and obstructive CAD according to findings of the CCTA. The findings of the groups were compared. Results: Eighty-five patients were enrolled in the study. Of them, 21 (26%) patients were female. Sixty-three patients (74%) had normal coronary arteries as per CCTA results, whereas 22 patients (22%) had nonobstructive CAD and two patients (2%) had obstructive CAD. The groups did not differ statistically in respect to hs-cTnT measurements, duration of the arrhythmia, and maximum heart rate at SVT episode. There was no significant statistical correlation between hs-cTnT and the study parameters except the maximum heart rate. Conclusion: Cardiac troponins may increase in patients with paroxysmal SVT irrespective of the presence of coronary lesions, and the CCTA may not be an appropriate investigation in the differential diagnosis of paroxysmal SVT with elevated hs-cTnT.

Hypertension in Middle Eastern Arab and South Asian Patients with Atrial Fibrillation: From a 20-Year Hospital Registry in Qatar (1990-2010).

Background: The vast majority of literature on atrial fibrillation (AF) is based on studies from the developed world that mainly includes Caucasian patients. Data on AF in other ethnicities is very limited. The aim of this hospital-based study is to evaluate the effect of concomitant hypertension (HTN) on the characteristics and outcomes of Middle Eastern Arab and South Asian patients with AF in the state of Qatar. Materials and Methods and Results: During the 20-year period, 3850 AF patients were hospitalized; 1483 (38.5%) had HTN, and 2367 (61.5%) without HTN. Patients with HTN were 11 years older, compared to non-HTN patients, and had a significantly higher prevalence of diabetes mellitus, chronic kidney disease, and dyslipidemia, compared to non-HTN patients. Furthermore, underlying coronary artery disease and heart failure were significantly more common but not valvular and rheumatic heart diseases which were more common in those without HTN. The rates of in-hospital mortality and stroke were significantly higher in the presence of HTN (5.3% versus 3.5%, and 0.7% versus 0.2% respectively, P = 0.001), compared to non-HTN patients. Conclusions: HTN is significantly associated with more comorbidities and worse clinical outcomes when it coexists with AF in hospitalized Middle Eastern Arab and South Asian patients.

Impact of COVID-19 upon changes in emergency room visits with chest pain of possible cardiac origin.

OBJECTIVES: A decrease in Emergency Department (ED) visits for cardiac conditions has recently been reported from the US and Western Europe due to the COVID-19 pandemic. The data are still scant, and the correlation between cardiac symptoms and confirmed diagnoses are not available. There are no reports on changes in ED volumes at a national level, or from countries in the Asia-Middle Eastern region. We report data from national referral centers for tertiary care and cardiac care centers in Qatar, which see > 80% of cardiac emergencies in the country. RESULTS: We analyzed 102,033 ED visits in the COVID-19-era (March-April 2020 and 2019) and determined the proportion presenting for cardiac symptoms and their confirmed diagnoses. We observed a 16-37% decline in ED volumes overall, with a 25-50% decline in patients presenting with cardiac symptoms in March and April 2020 compared with March and April 2019. Among those presenting with cardiac symptoms, we observed a 24-43% decline in cardiac diagnoses in March and April 2020 compared with March and April 2019.