Deleterious Effects of Cold Air Inhalation on Coronary Physiological Indices in Patients With Obstructive Coronary Artery Disease.
J Am Heart Assoc
; 7(14): e008837, 2018 07 17.
Article
en En
| MEDLINE
| ID: mdl-30762468
ABSTRACT
Background Cold air inhalation during exercise increases cardiac mortality, but the pathophysiology is unclear. During cold and exercise, dual-sensor intracoronary wires measured coronary microvascular resistance ( MVR ) and blood flow velocity ( CBF ), and cardiac magnetic resonance measured subendocardial perfusion. Methods and Results Forty-two patients (62±9 years) undergoing cardiac catheterization, 32 with obstructive coronary stenoses and 10 without, performed either (1) 5 minutes of cold air inhalation (5°F) or (2) two 5-minute supine-cycling periods 1 at room temperature and 1 during cold air inhalation (5°F) (randomized order). We compared rest and peak stress MVR , CBF , and subendocardial perfusion measurements. In patients with unobstructed coronary arteries (n=10), cold air inhalation at rest decreased MVR by 6% ( P=0.41), increasing CBF by 20% ( P<0.01). However, in patients with obstructive stenoses (n=10), cold air inhalation at rest increased MVR by 17% ( P<0.01), reducing CBF by 3% ( P=0.85). Consequently, in patients with obstructive stenoses undergoing the cardiac magnetic resonance protocol (n=10), cold air inhalation reduced subendocardial perfusion ( P<0.05). Only patients with obstructive stenoses performed this protocol (n=12). Cycling at room temperature decreased MVR by 29% ( P<0.001) and increased CBF by 61% ( P<0.001). However, cold air inhalation during cycling blunted these adaptations in MVR ( P=0.12) and CBF ( P<0.05), an effect attributable to defective early diastolic CBF acceleration ( P<0.05) and associated with greater ST -segment depression ( P<0.05). Conclusions In patients with obstructive coronary stenoses, cold air inhalation causes deleterious changes in MVR and CBF . These diminish or abolish the normal adaptations during exertion that ordinarily match myocardial blood supply to demand.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Consumo de Oxígeno
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Velocidad del Flujo Sanguíneo
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Frío
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Circulación Coronaria
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Vasos Coronarios
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Estenosis Coronaria
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Electrocardiografía
Tipo de estudio:
Diagnostic_studies
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Observational_studies
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Prognostic_studies
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Risk_factors_studies
Límite:
Female
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Humans
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Male
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Middle aged
Idioma:
En
Revista:
J Am Heart Assoc
Año:
2018
Tipo del documento:
Article