Bio

Clinical Focus


  • Pediatric Cardiology
  • Cardiology (Heart), Pediatric
  • Echocardiography
  • Echocardiography, Transesophageal

Academic Appointments


Professional Education


  • Fellowship:James Whitcomb Riley Hospital for Children (1997) IN
  • Residency:James Whitcomb Riley Hospital for Children (1994) IN
  • Board Certification: Pediatric Cardiology, American Board of Pediatrics (2000)
  • Internship:James Whitcomb Riley Hospital for Children (1992) IN
  • Medical Education:University of Kansas School of Medicine (1991) KS
  • B.A., University of Kansas, Microbiology and Human Biology (1987)
  • M.D., University of Kansas (1991)

Teaching

2013-14 Courses


Publications

Journal Articles


  • Supine cycling in pediatric exercise testing: disparity in performance measures. Pediatric cardiology May, L. J., Punn, R., Olson, I., Kazmucha, J. A., Liu, M. Y., Chin, C. 2014; 35 (4): 705-710

    Abstract

    Supine cycling may be an important alternative modality for exercise testing. Subtle differences in supine and upright exercise physiology have been suggested but not fully explored in the pediatric population. The aim of this study was to compare peak and submaximal metabolic data in the upright and supine exercise positions. Healthy children (N = 100) performed cardiopulmonary exercise tests using supine and upright cycle ergometry. Recruitment was governed by grant funding and not based on sample size calculations. Subjects exercised to exhaustion. Paired Student's t-tests were used to compare upright and supine data; simple linear regression analyses examined correlations between the two modalities. Peak heart rate was similar in both testing positions. Although peak oxygen uptake (peak VO2), oxygen uptake at anaerobic threshold (VO2@AT), VO2 when the respiratory exchange ratio is consistently at or above 1.0 (VO2@RER1.0), and the oxygen uptake efficiency slope were significantly higher in the upright position, no difference was considered of practical significance when applying Cohen's effect size criteria. Therefore, it may be reasonable for pediatric exercise laboratories to use established normative data and predictions for upright cycling position and apply them to metabolic measures obtained in supine exercise testing. Supine cycling with submaximal parameters may allow objective assessment of exercise capacity in children who undergo exercise echocardiography or cannot perform upright exercise testing.

    View details for DOI 10.1007/s00246-013-0841-y

    View details for PubMedID 24253612

  • Coronary Sinus Obstruction after Atrioventricular Canal Defect Repair. Congenital heart disease Peng, D. M., Sun, H. Y., Hanley, F. L., Olson, I., Punn, R. 2013

    Abstract

    The coronary sinus can become obstructed with any instrumentation at or near the ostium such as in atrioventricular canal defect repairs. This complication may lead to a wide range of consequences including dyspnea, angina, myocardial infarction, and sudden death. The following report illustrates the importance of careful perioperative echocardiographic evaluation of the coronary sinus in procedures that may affect the sinus and its ostium.

    View details for PubMedID 23682752

  • Supine Exercise Echocardiographic Measures of Systolic and Diastolic Function in Children JOURNAL OF THE AMERICAN SOCIETY OF ECHOCARDIOGRAPHY Punn, R., Obayashi, D. Y., Olson, I., Kazmucha, J. A., Depucci, A., Hurley, M. P., Chin, C. 2012; 25 (7): 773-781

    Abstract

    Echocardiography has been used to determine ventricular function, segmental wall motion abnormality, and pulmonary artery pressure before and after peak exercise. No prior study has investigated systolic and diastolic function using echocardiography at various phases of exercise in children. The aim of this study was to determine the fractional shortening (FS), systolic-to-diastolic (S/D) ratio, heart rate-corrected velocity of circumferential fiber shortening (VCFc), circumferential wall stress (WS), ratio of mitral passive inflow to active inflow (E/A), ratio of passive inflow by pulsed-wave to tissue Doppler (E/E'), and right ventricular-to-right atrial pressure gradient from tricuspid valve regurgitation jet velocity (RVP) and time duration at various phases of exercise in children.In an 8-month period (December 2007 to July 2008), 100 healthy children were evaluated, and 97 participants aged 8 to 17 years who performed complete cardiopulmonary exercise stress tests using supine cycle ergometry were prospectively enrolled. The participants consisted of 48 female and 49 male subjects with various body sizes, levels of exercise experience, and physical capacities. The cardiopulmonary exercise stress test consisted of baseline pulmonary function testing, continuous gas analysis and monitoring of blood pressure and heart rate responses, electrocardiographic recordings, and oxygen saturation measurement among participants who pedaled against a ramp protocol based on body weight. All participants exercised to exhaustion. Echocardiography was performed during exercise at baseline, at a heart rate of 130 beats/min, at a heart rate of 160 beats/min, at 5 min after exercise, and at 10 min after exercise. FS, S/D ratio, VCFc, WS, E/A, E', E/E', and RVP at these five phases were compared in all subjects.All echocardiographic parameters differed at baseline from 160 beats/min (P < .0001) except E/E', which remained at 5.4 to 5.8. Specifically, FS (from 37% to 46%), S/D ratio, VCFc (from 1.1 to 1.6), WS (from 200 to 258 g/cm(2)), E' (from 0.2 to 0.3), and RVP (from 18 to 35 mm Hg) increased from baseline to 160 beats/min and then subsequently decreased to at or near baseline, while tricuspid valve regurgitation duration decreased (from 370 to 178 msec).Normal values for systolic and diastolic echocardiographic measurements of function are now available. FS, VCFc, WS, and RVP increase with exercise and then return to near baseline levels. The E/E' ratio is unaltered with exercise in normal subjects.

    View details for DOI 10.1016/j.echo.2012.03.007

    View details for Web of Science ID 000305701600013

    View details for PubMedID 22521368

  • Correlation of Subjective Questionnaires With Cardiac Function as Determined by Exercise Testing in a Pediatric Population PEDIATRIC CARDIOLOGY Burns, R., Olson, I., Kazmucha, J., Balise, R., Chin, R., Chin, C. 2010; 31 (7): 1043-1048

    Abstract

    Although exercise testing is an important objective method used to assess cardiopulmonary function, subjective assessment often is used as a proxy in the clinical setting. This study aimed to determine whether responses to a subjective functional capacity questionnaire administered to parents and patients in a pediatric exercise laboratory correlate with objective assessment of functional capacity, measured by peak oxygen consumption during maximal voluntary exercise testing.Subjective questionnaire responses and exercise test results collected over 10 years were retrospectively analyzed. Symptoms and physical capabilities were assessed using a 6-point Likert scale regarding the ability to attend school/work, walk, climb stairs, and run, as well as the frequency of fatigue, palpitations, and chest pain. Values of 0 to 3 were considered abnormal, whereas values of 4-5 were regarded as normal. Exercise testing was performed on a stationary cycle ergometer with a continuous ramping protocol. Heart rate and oxygen saturation were continuously monitored. Blood pressures and electrocardiograms (ECGs) were obtained at 2-min intervals. Metabolic gas analysis was performed using a breath-by-breath method. The results of the exercise testing were normalized for body size and expressed as a percentage of predicted peak oxygen consumption (%pVO(2)).Very weak but statistically significant correlations (? < 0.25; P < 0.05) between the scores of the school/work, walking, stair climbing, running, and fatigue items and %pVO(2) were found using Kendall's rank correlations.The subjective Likert scales used to assess basic physical capacity and cardiac-associated symptoms have limited ability to predict actual functional capacity as measured by %pVO(2) achieved. The very weak rank-order correlation between %pVO(2) achieved and the subjective reporting of the ability to attend school/work, walk, climb stairs, and run has low clinical significance and will not be useful in predicting functional capacity within the clinic setting.

    View details for DOI 10.1007/s00246-010-9761-2

    View details for Web of Science ID 000282424800015

    View details for PubMedID 20811883

  • Anomalies Associated With a Prominent Azygos Vein on Echocardiography in the Pediatric Population JOURNAL OF THE AMERICAN SOCIETY OF ECHOCARDIOGRAPHY Punn, R., Olson, I. 2010; 23 (3): 282-285

    Abstract

    Prominent azygos veins (PAVs) have been described with interrupted inferior venae cavae (IVCs) with heterotaxy. At the authors' institution, cases of PAVs with uninterrupted IVCs have been noted. The aim of this study was to determine the occurrence rate of PAVs and associated lesions by echocardiography.All patients with PAVs were collected; those with interrupted and uninterrupted IVCs were assigned to groups 1 and 2. Normal controls were assigned to group 3.Among 15,849 patients from January 1, 2001, to March 31, 2008, 55 (0.3%) had PAVs, 42 (76%) in group 1 and 13 (24%) in group 2. Heterotaxy was prominent in group 1, whereas patients in group 2 had no heterotaxy. Patients in group 2 had more structurally normal hearts than those in group 1 (46% vs 14%, P<.01), partial anomalous pulmonary venous return, and one single ventricle. IVC measurements were the same in groups 2 and 3 (P=.65).This study demonstrates that a PAV without IVC interruption is not associated with heterotaxy. Patients with PAVs should be carefully examined for partial anomalous pulmonary venous return.

    View details for DOI 10.1016/j.echo.2009.11.025

    View details for Web of Science ID 000275221900007

    View details for PubMedID 20138465

  • V-O2 @ RER1.0: A Novel Submaximal Cardiopulmonary Exercise Index PEDIATRIC CARDIOLOGY Chin, C., Kazmucha, J., Kim, N., Suryani, R., Olson, I. 2010; 31 (1): 50-55

    Abstract

    Maximal oxygen consumption (VO2max) is the "gold standard" by which to assess functional capacity; however, it is effort dependent. VO2@RER1.0 is defined when VO2 = VCO2. Between December 22, 1997 and November 9, 2004, 305 pediatric subjects underwent cycle ergometer cardiopulmonary exercise testing, exercised to exhaustion, and reached a peak respiratory exchange ratio > or = 1.10. Group 1 subjects achieved a peak VO2 > or = 80% of predicted VO2max; group 2 subjects achieved a peak VO2 < or = 60% of predicted VO2max; and group 3 subjects achieved a peak VO2 between 61 and 79% of predicted VO2max. Linear regression analysis was performed for VO2@RER1.0 as a function of predicted VO2 for group 1 subjects. A -2 SD regression line and equation was created. VO2@RER1.0 data from groups 2 and 3 were plotted onto the normative graph. Contingency table and relative-risk analysis showed that an abnormal VO2@RER1.0 predicted an abnormal peak VO2(positive-predictive value 83%, negative-predictive value 85%, sensitivity 84%, and specificity 84%). VO2@RER1.0 is a highly sensitive, specific, and predictive submaximal index of functional capacity. This submaximal index is easy to identify without subjectivity. This index may aid in the evaluation of subjects who cannot exercise to maximal parameters.

    View details for DOI 10.1007/s00246-009-9544-9

    View details for Web of Science ID 000273675400010

    View details for PubMedID 19812880

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