RESUMO
Recent invasive studies using intracoronary Doppler catheters or guide wires reported improved coronary flow dynamics after successful percutaneous transluminal coronary angioplasty. Transesophageal Doppler enables the measurement of coronary flow velocities within the left anterior descending artery. The present study was designed to test: (1) whether transesophageal Doppler may detect coronary flow velocity changes in patients undergoing angioplasty for left anterior descending artery stenosis, and (2) whether this technique may help to evaluate non-invasively the results of the procedure. Twenty-three patients undergoing angioplasty of the left anterior descending artery were studied by transesophageal Doppler before and < or = 24 hours after the interventional procedure. Coronary flow velocities were measured in the proximal part of the left anterior descending artery with the use of pulsed Doppler guided by color flow imaging. The degree of stenosis was measured by computerized quantitative coronary arteriography. Coronary flow velocity signals were successfully obtained in 19 of 23 patients (83%). In 16 successful angioplasty procedures, peak diastolic velocity increased from 37 +/- 14 cm/s before angioplasty to 51 +/- 16 cm/s after (p = 0.0001). In the 3 patients in whom angioplasty was unsuccessful, transesophageal Doppler showed no significant increase in peak diastolic coronary flow velocity. In a total of 19 angioplasty procedures, a good linear relation was found between the percent changes in coronary flow diastolic velocity and the reduction in the degree of stenosis (r = 0.85; p = 0.0001). All patients with > 20% increase in peak diastolic velocity had > 40% stenosis reduction.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Angioplastia Coronária com Balão , Circulação Coronária/fisiologia , Doença das Coronárias/diagnóstico por imagem , Ecocardiografia Transesofagiana , Idoso , Velocidade do Fluxo Sanguíneo/fisiologia , Doença das Coronárias/fisiopatologia , Doença das Coronárias/terapia , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Fatores de TempoRESUMO
The aim of this study was to determine whether previous angina pectoris and collateral circulation influenced myocardial function after isolated coronary occlusion. In 58 consecutive patients, coronary angiography showed a complete isolated occlusion of the left anterior descending coronary artery; 43 patients (74%) had previous myocardial infarction. Duration of previous angina pectoris was defined as the time from the first ischemic symptom to the date of myocardial infarction or of coronary angiography in the absence of myocardial infarction. Left ventricular ejection fraction was measured on the 30 degrees right anterior oblique projection of the left ventricular angiogram. Collateral circulation was graded as follows: none or filling limited to side branches (group 1) and partial or complete filling of the epicardial arterial segment (group 2). Group 2 (40 patients) had higher ejection fraction (57 vs 38%; p less than 0.0001) and longer duration of previous angina pectoris (11 vs 0.1 months; p less than 0.002) than group 1 (18 patients). A longer duration of previous angina pectoris probably allows collateral development before coronary occlusion in 1-vessel coronary artery disease, thereby limiting myocardial damage.
Assuntos
Angina Pectoris/fisiopatologia , Circulação Colateral/fisiologia , Doença das Coronárias/fisiopatologia , Infarto do Miocárdio/fisiopatologia , Angiografia , Angiografia Coronária , Circulação Coronária/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Contração Miocárdica/fisiologia , Volume Sistólico/fisiologia , Fatores de TempoRESUMO
The clinical profile of coronary patients admitted to cardiac rehabilitation centres after myocardial infarction has changed considerably in the last 15 years. Complementary investigations (coronary angiography, studies of left ventricular function) provide accurate information which improves the process of rehabilitation. Global management of the coronary patient requires and justifies, especially in young adults, taking into consideration the physical, psychological and socio-professional consequences of a myocardial infarction. The indications of rehabilitation are much more comprehensive nowadays. Even patients with significant haemodynamic impairment can benefit from a stay in a specialised centre. Contraindications are usually only temporary. Finally, an enquiry performed in 33 French cardiac rehabilitation centres shows large variations in methods, personnel and organisation. However, as a general rule, a 3 week stay seems to be adequate but it is logical to continue rehabilitation when the patients goes home to pursue and maintain at long term the results obtained on discharge from a specialised centre.