[Show abstract][Hide abstract] ABSTRACT: Focus Areas: Integrative Approaches to Care, Supporting Behavioral Change, Alleviating Pain
Mindfulness-based stress reduction (MBSR) is a well-delineated 8-week mindfulness meditation program and hence lends itself well to be applied clinically and studied systematically.
Heart rate variability (HRV) is the beat-to-beat variation in the heart rate and is a unique way to study sympathovagal balance and autonomic control of cardiopulmonary dynamics.
Twenty healthy volunteers were recruited from among participants of the MBSR program offered at the University of Minnesota. Two visits are planned, before and after completion of the MBSR program.
After a brief period to help subjects acclimatize, 3 phases of data were recorded, each phase lasting for 5 minutes.
Phase 1. Resting: Served as baseline value.Phase 2. Controlled Respiration: Involved audio cues to control the respiratory rate at a fixed interval of 6/minute.Phase 3. Meditation:Involved self-guided sitting meditation.Echocardiogram, respiration, and skin temperature were recorded continuously throughout each phase. Each subject will serve as his/her own control.
Change in the standard deviation of normal-normal RR intervals (SDNN), measure of HRV total power, during a state of meditation (phase 3) at the completion of the MBSR program. Change in SDNN during a resting, non-meditative state (phase 1) at the completion of the MBSR program. Change in SDNN between controlled respiration (phase 2) and meditation (phase 3) after completion of the MBSR program. Change in Perceived Stress Scale score.
Volunteers will return for their final visit after completion of the MBSR course in June 2013. With the knowledge gained from this pilot study, we hope to study the effects of the MBSR program in patients with established cardiovascular disease conditions in which sympatho-vagal imbalance is known to play some role in causation, namely myocardial infarction, heart failure, and hypertension.
[Show abstract][Hide abstract] ABSTRACT: Left ventricular non-compaction (LVNC) cardiomyopathy is a rare congenital disorder, classified by the American Heart Association as a primary genetic cardiomyopathy and characterized by multiple trabeculations within the left ventricle. LVNC cardiomyopathy has been associated with 3 major clinical manifestations: heart failure, atrial and ventricular arrhythmias and thromboembolic events, including stroke. In this case report, we describe a female patient with apparently isolated LVNC in whom pause-dependent polymorphic ventricular tachycardia suggesting torsades de pointes occurred in the presence of a normal QT interval.
Full-text · Article · Feb 2013 · Journal of Arrhythmia
[Show abstract][Hide abstract] ABSTRACT: BACKGROUND: Although vasovagal syncope (VVS) is preceded by a surge of circulating catecholamines (epinephrine [Epi] and norepinephrine [NE]) of adrenal/renal and synaptic origin, prevention of VVS with β-adrenergic blockade has been ineffective except in "older" VVS patients. OBJECTIVE: We hypothesized that age-related differences of β-blocker effect may be due in part to differences in the relative magnitudes of Epi and NE release during an evolving faint, specifically, greater Epi/NE ratio in younger fainters compared to older patients. To assess this hypothesis, we measured changes in Epi/NE ratios in younger (<40 years) vs older (≥40 years) patients during head-up tilt-table test-induced VVS. METHODS: The study comprised 29 patients (12 patients ≥40 years [mean 56 ± 10.7 years] and 17 patients <40 years mean 25 ± 5.7 years]) with recurrent suspected VVS in whom 70° head-up tilt testing reproduced symptoms. Arterial Epi and NE concentrations were measured at baseline (supine), 2 minutes of head-up tilt, and syncope. RESULTS: Baseline Epi and NE concentrations and the Epi/NE ratio did not differ in younger and older groups (Epi: 90 ± 65 pg/mL vs 70 ± 32 pg/mL; NE: 226 ± 122 pg/mL vs 244 ± 183 pg/mL). However, Epi/NE ratio increased to a greater extent in younger fainters during head-up tilt and tended to be greater in younger patients at both 2 minutes (<40: 1.02 ± 1.29 vs ≥40: 0.40 ± 0.27, P = .11) and at symptoms (<40: 2.6 ± 1.26 vs ≥40: 1.6 ± 0.71, P = .03). At symptoms, Epi/NE ratio ≥2.5 was observed in 9 of 17 younger patients vs 1 of 12 older patients (P = .02). CONCLUSION: Epi/NE ratios tend to be greater in younger fainters, a finding that may account in part for the observation that β-blocker therapy is less effective in reducing VVS susceptibility in younger individuals.
No preview · Article · Jul 2012 · Heart rhythm: the official journal of the Heart Rhythm Society
[Show abstract][Hide abstract] ABSTRACT: Vasodepressor Cough Syncope. Cough syncope is classified among the neural-reflex "situational" faints, but whether the clinical consequences in affected individuals result from reflex triggered bradyarrhythmia or vasodepressor-induced hypotension, or both, is often unknown. In this report we describe findings in a patient with a clinical history consistent with cough syncope, and in whom documented multiple asystolic spells were at first believed to be responsible for symptoms. However, pacemaker therapy initiated at an outside facility failed to suppress symptoms, and subsequent referral for more detailed autonomic study revealed the asystole to be due to sleep apnea, whereas cough-induced vasodepressor hypotension was the basis of syncope in this individual; the latter provided a pathophysiologic target for prevention of recurring symptoms. (J Cardiovasc Electrophysiol, Vol. 23, pp. 1024-1027, September 2012).
No preview · Article · Apr 2012 · Journal of Cardiovascular Electrophysiology