Evidence of a dominant backward-propagating "suction" wave responsible for diastolic coronary filling in humans, attenuated in left ventricular hypertrophy.
Circulation
; 113(14): 1768-78, 2006 Apr 11.
Article
em En
| MEDLINE
| ID: mdl-16585389
ABSTRACT
BACKGROUND:
Coronary blood flow peaks in diastole when aortic blood pressure has fallen. Current models fail to completely explain this phenomenon. We present a new approach-using wave intensity analysis-to explain this phenomenon in normal subjects and to evaluate the effects of left ventricular hypertrophy (LVH). METHOD ANDRESULTS:
We measured simultaneous pressure and Doppler velocity with intracoronary wires in the left main stem, left anterior descending, and circumflex arteries of 20 subjects after a normal coronary arteriogram. Wave intensity analysis was used to identify and quantify individual pressure and velocity waves within the coronary artery circulation. A consistent pattern of 6 predominating waves was identified. Ninety-four percent of wave energy, accelerating blood forward along the coronary artery, came from 2 waves first a pushing wave caused by left ventricular ejection-the dominant forward-traveling pushing wave; and later a suction wave caused by relief of myocardial microcirculatory compression-the dominant backward-traveling suction wave. The dominant backward-traveling suction wave (18.2+/-13.7 x 10(3) W m(-2)s(-1), 30%) was larger than the dominant forward-traveling pushing wave (14.3+/-17.6 x 10(3) W m(-2) s(-1), 22.3%, P =0.001) and was associated with a substantially larger increment in coronary blood flow velocity (0.51 versus 0.14 m/s, P <0.001). In LVH, the dominant backward-traveling suction wave percentage was significantly decreased (33.1% versus 26.9%, P =0.01) and inversely correlated with left ventricular septal wall thickness (r =-0.52, P <0.02).CONCLUSIONS:
Six waves predominantly drive human coronary blood flow. Coronary flow peaks in diastole because of the dominance of a "suction" wave generated by myocardial microcirculatory decompression. This is significantly reduced in LVH.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Hipertrofia Ventricular Esquerda
/
Circulação Coronária
/
Contração Miocárdica
Limite:
Adult
/
Female
/
Humans
/
Male
/
Middle aged
Idioma:
En
Revista:
Circulation
Ano de publicação:
2006
Tipo de documento:
Article
País de afiliação:
Reino Unido