Dr. Raina is a board-certified cardiologist in the General Cardiology clinic at Stanford Health Care and a member of the Stanford Cardiovascular Institute. He is also a clinical associate professor in the Division of Cardiovascular Medicine.

His clinical interests include preventive cardiology, cardiac rehabilitation, and sports cardiology. In his recent positions at West Virginia University, he established the cardiology telemedicine program during and after the COVID pandemic. He applied his passion for cardiac rehab by creating individualized treatment plans for college athletes recovering from COVID. Dr. Raina is also passionate about building relationships with community doctors. He believes continuous communication is an essential part of excellent patient care.

Dr. Raina’s current research focuses on preventive cardiology, cardiac imaging, and outcomes research. He studies the outcomes of different cardiac interventions in specific patient populations. His research helps identify appropriate treatments for patients who have other conditions in addition to heart disease.

Dr. Raina eagerly anticipates joining the faculty of the Stanford South Asian Translational Heart Initiative (SSATHI). He is excited for the opportunity to address the high risk of cardiovascular diseases among South Asians. He looks forward to applying his clinical and research experience to support SSATHI’s mission to provide advanced care to ethnic populations disproportionately affected by these diseases.

Dr. Raina is a peer reviewer for several prestigious publications, including Neuropsychiatric Disease and Treatment and the International Journal of Chronic Obstructive Pulmonary Disease. He has also been an invited guest speaker at national and international meetings, including those for the International Congress of Cardiology and the World Congress of Cardiothoracic-Renal Diseases.

Dr. Raina is a fellow of the American College of Cardiology (FACC) and a member of the American College of Cardiology.

Clinical Focus

  • Cardiovascular Disease

Academic Appointments

Honors & Awards

  • Darden Merit Scholarship for Outstanding Academic Performance, University of Virginia Darden School of Business

Professional Education

  • Board Certification: American Board of Internal Medicine, Cardiovascular Disease (2024)
  • Board Certification: Certification Board of Nuclear Cardiology, Nuclear Cardiology
  • Board Certification: National Board of Echocardiography, Adult Echocardiography (2016)
  • Fellowship: University of Arkansas for Medical Sciences Medical Center (2016) AR
  • Residency: University of Arkansas Internal Medicine (2013) AR
  • Medical Education: Armed Forces Medical College (2004) India

All Publications

  • Contemporary trends of leadless pacemaker implantation in the United States. Journal of cardiovascular electrophysiology Khan, M. Z., Nassar, S., Nguyen, A., Khan, M. U., Sattar, Y., Alruwaili, W., Gonuguntla, K., Mazek, H., Asad, Z. U., Agarwal, S., Raina, S., Balla, S., Nguyen, B., Fan, D., Darden, D., Munir, M. B. 2024


    INTRODUCTION: Leadless pacemakers (LPM) have established themselves as the important therapeutic modality in management of selected patients with symptomatic bradycardia. To determine real-world utilization and in-hospital outcomes of LPM implantation since its approval by the Food and Drug Administration in 2016.METHODS: For this retrospective cohort study, data were extracted from the National Inpatient Sample database from the years 2016-2020. The outcomes analyzed in our study included implantation trends of LPM over study years, mortality, major complications (defined as pericardial effusion requiring intervention, any vascular complication, or acute kidney injury), length of stay, and cost of hospitalization. Implantation trends of LPM were assessed using linear regression. Using years 2016-2017 as a reference, adjusted outcomes of mortality, major complications, prolonged length of stay (defined as >6 days), and increased hospitalization cost (defined as median cost >34098$) were analyzed for subsequent years using a multivariable logistic regression model.RESULTS: There was a gradual increased trend of LPM implantation over our study years (3230 devices in years 2016-2017 to 11815 devices in year 2020, p for trend <.01). The adjusted mortality improved significantly after LPM implantation in subsequent years compared to the reference years 2016-2017 (aOR for the year 2018: 0.61, 95% CI: 0.51-0.73; aOR for the year 2019: 0.49, 95% CI: 0.41-0.59; and aOR for the year 2020: 0.52, 95% CI: 0.44-0.62). No differences in adjusted rates of major complications were demonstrated over the subsequent years. The adjusted cost of hospitalization was higher for the years 2019 (aOR: 1.33, 95% CI: 1.22-1.46) and 2020 (aOR: 1.69, 95% CI: 1.55-1.84).CONCLUSION: The contemporary US practice has shown significantly increased implantation rates of LPM since its approval with reduced rates of inpatient mortality.

    View details for DOI 10.1111/jce.16295

    View details for PubMedID 38695242

  • Association of Chronic Kidney Disease and End-Stage Renal Disease with Procedural Complications and Inpatient Outcomes of Leadless Pacemaker Implantations Across the United States. Heart rhythm Khan, M. Z., Nguyen, A., Khan, M. U., Sattar, Y., Alruwaili, W., Gonuguntla, K., Sohaib Hayat, H. M., Mendez, M., Nassar, S., Asad, Z. U., Agarwal, S., Raina, S., Balla, S., Nguyen, B., Fan, D., Darden, D., Munir, M. B. 2024


    Leadless pacemakers have emerged as a promising alternative to transvenous pacemakers in patients with kidney disease. However, studies investigating leadless pacemaker outcomes and complications based on kidney dysfunction are limited.To evaluate the association of chronic kidney disease (CKD) and end-stage renal disease (ESRD) with inpatient complications and outcomes of leadless pacemaker implantations.National Inpatient Sample and International Classification of Diseases, Tenth Revision codes were used to identify CKD and ESRD patients who underwent leadless pacemaker implantations in the U.S. from 2016-2020. Study endpoints assessed included inpatient complications, outcomes and resource utilization of leadless pacemaker implantations.A total of 29,005 leadless pacemaker placements were identified. Patients with CKD (n=5,245, 18.1%) and ESRD (n=3,790, 13.1%) were younger and had higher prevalence of important comorbidities than patients without CKD. In crude analysis, ESRD was associated with higher prevalence of major complications, peripheral vascular complications, and inpatient mortality. After multivariable adjustment, CKD and ESRD were associated with inpatient mortality (aOR 1.62, 95% CI 1.40 - 1.86; aOR 1.38, 95% CI 1.18 - 1.63) and prolonged length of stay (aOR 1.55, 95% CI 1.46 - 1.66; aOR 1.81, 95% CI 1.67 - 1.96). ESRD was also associated with higher hospitalization costs (aOR 1.63, 95% CI 1.50 - 1.77) and major complications (aOR 1.62, 95% CI 1.40 - 1.86) after leadless pacemaker implantation.Approximately one-third of patients undergoing leadless pacemaker implantation had CKD or ESRD. CKD and ESRD were associated with greater length and cost of stay, and inpatient mortality.

    View details for DOI 10.1016/j.hrthm.2024.03.1816

    View details for PubMedID 38574789

  • Pericardial effusion requiring intervention in patients undergoing leadless pacemaker implantation: A real-world analysis from the National Inpatient Sample database. Heart rhythm O2 Khan, M. Z., Sattar, Y., Alruwaili, W., Nassar, S., Alhajji, M., Alyami, B., Nguyen, A. T., Neely, J., Abideen Asad, Z. U., Agarwal, S., Raina, S., Balla, S., Nguyen, B., Fan, D., Darden, D., Munir, M. B. 2024; 5 (4): 217-223


    Pericardial effusion requiring percutaneous or surgical-based intervention remains an important complication of a leadless pacemaker implantation.The study sought to determine real-world prevalence, risk factors, and associated outcomes of pericardial effusion requiring intervention in leadless pacemaker implantations.The National Inpatient Sample and International Classification of Diseases-Tenth Revision codes were used to identify patients who underwent leadless pacemaker implantations during the years 2016 to 2020. The outcomes assessed in our study included prevalence of pericardial effusion requiring intervention, other procedural complications, and in-hospital outcomes. Predictors of pericardial effusion were also analyzed.Pericardial effusion requiring intervention occurred in a total of 325 (1.1%) leadless pacemaker implantations. Patient-level characteristics that predicted development of a serious pericardial effusion included >75 years of age (odds ratio [OR] 1.38, 95% confidence interval [CI] 1.08-1.75), female sex (OR 2.03, 95% CI 1.62-2.55), coagulopathy (OR 1.50, 95% CI 1.12-1.99), chronic pulmonary disease (OR 1.36, 95% CI 1.07-1.74), chronic kidney disease (OR 1.53, 95% CI 1.22-1.94), and connective tissue disorders (OR 2.98, 95% CI 2.02-4.39). Pericardial effusion requiring intervention was independently associated with mortality (OR 5.66, 95% CI 4.24-7.56), prolonged length of stay (OR 1.36, 95% CI 1.07-1.73), and increased cost of hospitalization (OR 2.49, 95% CI 1.92-3.21) after leadless pacemaker implantation.In a large, contemporary, real-world cohort of leadless pacemaker implantations in the United States, the prevalence of pericardial effusion requiring intervention was 1.1%. Certain important patient-level characteristics predicted development of a significant pericardial effusion, and such effusions were associated with adverse outcomes after leadless pacemaker implantations.

    View details for DOI 10.1016/j.hroo.2024.02.004

    View details for PubMedID 38690142

    View details for PubMedCentralID PMC11056447

  • Takotsubo Cardiomyopathy and Psychiatric Illness- Insight from National Inpatient Sample (NIS) and National Re-admission Database (NRD) 2016 to 2018. Current problems in cardiology Gonuguntla, K., Thyagaturu, H., Shaik, A., Roma, N., Thangjui, S., Alruwaili, W., Patel, K. N., Nasser, S., Valand, H., Cheema, M. S., Jain, B., Ahmed, A., Raina, S., Ditah, C. M., Sattar, Y. 2024: 102429


    BACKGROUND: Emotional stress is a common precipitating cause of takotsubo cardiomyopathy (TC). Preexisting psychiatric disorder (PD) was linked to worsening outcomes in patients with TC1,2. However, there is limited data in literature to support this. This study aimed to determine the differences in outcomes in TC patients with and without PD.METHODS: We identified all patients with a diagnosis of TC using the National Inpatient Sample (NIS) and the National Readmission Database (NRD) data from 2016 to 2018. The patients were separated into TC with PD group and TC without PD group. Multiple variable logistic regression was then performed.RESULTS: Using NIS 2016-2018, we identified 23,220 patients with TC, and 43.11% had PD. The mean age was 66.73 ± 12.74 years, with 90.42% being female sex. The TC with PD group had a higher 30-readmission rate 1.25 (95% CI:1.06-1.47), Cardiogenic shock [aOR = 7.3 (95%CI 3.97-13.6), Mechanical ventilation [aOR = 4.2 (95%CI 2.4-7.5), Cardiac arrest [aOR = 2.6 (95%CI 1.1-6.3), than TC without PD group.CONCLUSION: Psychiatric disorders were found in up to 43% of patients with TC. The concomitant PD in TC patients was not associated with increased mortality, AKI, but had higher rates of cardiogenic shock, use of mechanical ventilation and cardiac arrest. The TC group with PD was also associated with increased 30-day readmission, LOS and total charges compared to TC patients without PD.

    View details for DOI 10.1016/j.cpcardiol.2024.102429

    View details for PubMedID 38331372

  • Trends and Outcomes of Type 2 Myocardial Infarction During the COVID-19 Pandemic in the United States. Korean circulation journal Thyagaturu, H., Roma, N., Angirekula, A., Thangjui, S., Bolton, A., Gonuguntla, K., Sattar, Y., Chobufo, M. D., Challa, A., Patel, N., Bondi, G., Raina, S. 2023


    BACKGROUND AND OBJECTIVES: There is limited data on the impact of type 2 myocardial infarction (T2MI) during the coronavirus disease 2019 (COVID-19) pandemic.METHODS: The National Inpatient Sample (NIS) database from January 2019 to December 2020 was queried to identify T2MI hospitalizations based on the appropriate International Classification of Disease, Tenth Revision-Clinical Modification codes. Monthly trends of COVID-19 and T2MI hospitalizations were evaluated using Joinpoint regression analysis. In addition, the multivariate logistic and linear regression analysis was used to compare in-hospital mortality, coronary angiography use, and resource utilization between 2019 and 2020.RESULTS: A total of 743,535 patients hospitalized with a diagnosis of T2MI were identified in the years 2019 (n=331,180) and 2020 (n=412,355). There was an increasing trend in T2MI hospitalizations throughout the study period corresponding to the increase in COVID-19 hospitalizations in 2020. The adjusted odds of in-hospital mortality associated with T2MI hospitalizations were significantly higher in 2020 compared with 2019 (11.1% vs. 8.1%: adjusted odds ratio, 1.19 [1.13-1.26]; p<0.01). In addition, T2MI hospitalizations were associated with lower odds of coronary angiography and higher total hospitalization charges, with no difference in the length of stay in 2020 compared with 2019.CONCLUSIONS: We found a significant increase in T2MI hospitalizations with higher in-hospital mortality, total hospitalization costs, and lower coronary angiography use during the early COVID-19 pandemic corresponding to the trends in the rise of COVID-19 hospitalizations. Further research into the factors associated with increased mortality can increase our preparedness for future pandemics.

    View details for DOI 10.4070/kcj.2023.0063

    View details for PubMedID 37880873

  • Intracranial bleeding and associated outcomes in atrial fibrillation patients undergoing percutaneous left atrial appendage occlusion: Insights from National Inpatient Sample 2016-2020. Heart rhythm O2 Khan, M. Z., Shatla, I., Darden, D., Neely, J., Mir, T., Abideen Asad, Z. U., Agarwal, S., Raina, S., Balla, S., Singh, G. D., Srivatsa, U., Munir, M. B. 2023; 4 (7): 433-439


    Background: Percutaneous left atrial appendage occlusion (LAAO) has proved to be a safer alternative for long-term anticoagulation; however, patients with a history of intracranial bleeding were excluded from large randomized clinical trials.Objective: The purpose of this study was to determine outcomes in atrial fibrillation (AF) patients with a history of intracranial bleeding undergoing percutaneous LAAO.Methods: National Inpatient Sample and International Classification of Diseases, Tenth Revision, codes were used to identify patients with AF who underwent LAAO during the years 2016-2020. Patients were stratified based on a history of intracranial bleeding vs not. The outcomes assessed in our study included complications, in-hospital mortality, and resource utilization.Result: A total of 89,300 LAAO device implantations were studied. Approximately 565 implantations (0.6%) occurred in patients with a history of intracranial bleed. History of intracranial bleeding was associated with a higher prevalence of overall complications and in-patient mortality in crude analysis. In the multivariate model adjusted for potential confounders, intracranial bleeding was found to be independently associated with in-patient mortality (adjusted odds ratio [aOR] 4.27; 95% confidence interval [CI] 1.68-10.82); overall complications (aOR 1.74; 95% CI 1.36-2.24); prolonged length of stay (aOR 2.38; 95% CI 1.95-2.92); and increased cost of hospitalization (aOR 1.28; 95% CI 1.08-1.52) after percutaneous LAAO device implantation.Conclusion: A history of intracranial bleeding was associated with adverse outcomes after percutaneous LAAO. These data, if proven in a large randomized study, can have important clinical consequences in terms of patient selection for LAAO devices.

    View details for DOI 10.1016/j.hroo.2023.06.002

    View details for PubMedID 37520018