scholarly journals Differences in cardiac microcirculatory wave patterns between the proximal left mainstem and proximal right coronary artery

2008 ◽  
Vol 295 (3) ◽  
pp. H1198-H1205 ◽  
Author(s):  
Nearchos Hadjiloizou ◽  
Justin E. Davies ◽  
Iqbal S. Malik ◽  
Jazmin Aguado-Sierra ◽  
Keith Willson ◽  
...  
Keyword(s):  
Coronary Artery ◽  
Flow Velocity ◽  
Coronary Arteries ◽  
Right Coronary Artery ◽  
Coronary Flow ◽  
Wave Intensity ◽  
Intensity Analysis ◽  
Wave Intensity Analysis ◽  
Coronary Flow Velocity ◽  
Proximal Right Coronary Artery

Despite having almost identical origins and similar perfusion pressures, the flow-velocity waveforms in the left and right coronary arteries are strikingly different. We hypothesized that pressure differences originating from the distal (microcirculatory) bed would account for the differences in the flow-velocity waveform. We used wave intensity analysis to separate and quantify proximal- and distal-originating pressures to study the differences in velocity waveforms. In 20 subjects with unobstructed coronary arteries, sensor-tipped intra-arterial wires were used to measure simultaneous pressure and Doppler velocity in the proximal left main stem (LMS) and proximal right coronary artery (RCA). Proximal- and distal-originating waves were separated using wave intensity analysis, and differences in waves were examined in relation to structural and anatomic differences between the two arteries. Diastolic flow velocity was lower in the RCA than in the LMS (35.1 ± 21.4 vs. 56.4 ± 32.5 cm/s, P < 0.002), and, consequently, the diastolic-to-systolic ratio of peak flow velocity in the RCA was significantly less than in the LMS (1.00 ± 0.32 vs. 1.79 ± 0.48, P < 0.001). This was due to a lower distal-originating suction wave (8.2 ± 6.6 × 103 vs. 16.0 ± 12.2 × 103 W·m−2·s−1, P < 0.01). The suction wave in the LMS correlated positively with left ventricular pressure ( r = 0.6, P < 0.01) and in the RCA with estimated right ventricular systolic pressure ( r = 0.7, P = 0.05) but not with the respective diameter in these arteries. In contrast to the LMS, where coronary flow velocity was predominantly diastolic, in the proximal RCA coronary flow velocity was similar in systole and diastole. This difference was due to a smaller distal-originating suction wave in the RCA, which can be explained by differences in elastance and pressure generated between right and left ventricles.

scholarly journals Prognostic value of non-invasive coronary artery flow velocity assessment in elderly patients

2021 ◽  
Vol 22 (Supplement_1) ◽  
Author(s):  
E Kalinina ◽  
A Zagatina ◽  
N Zhuravskaya ◽  
D Shmatov
Keyword(s):  
Myocardial Infarction ◽  
Coronary Artery ◽  
Elderly Patients ◽  
Flow Velocity ◽  
Coronary Arteries ◽  
Coronary Flow ◽  
Prognostic Value ◽  
Area Under Curve ◽  
Left Coronary Artery ◽  
Maximal Velocity

Abstract Funding Acknowledgements Type of funding sources: None. Background There is a high prevalence of coronary artery disease (CAD) in the elderly population. However, symptoms of CAD are often non-specific. Dyspnoe, non-anginal pains are among the main symptoms in older patients. Exercise tests are of limited feasibility in these patients, due to neuro-muscular weakness, physical deconditioning, and orthopaedic limitations. Pharmacological tests often are contraindicated in a substantial percentage of elderly patients. Some recent studies indicate using local flow acceleration during routine echocardiography has prognostic potential for coronary artery assessments without stress testing. The aim of the study was to define the prognostic value of coronary artery ultrasound assessment in patients ≥75 years old. Methods This is a prospective cohort study. Patients ≥ 75 years old who underwent routine echocardiography with additional scans for coronary arteries over a period of 24 months were included in the study. The study group consisted of 80 patients aged 75-90 years (56 women; mean age 79 ± 4). Initial exams were performed for other reasons, primarily for arterial hypertension. Fifteen patients had known CAD. Death, non-fatal myocardial infarction (MI), and revascularization were defined as major adverse cardiac events (MACE). All patients were followed up with at a median of 32 months. Results There were 34 patients with high local velocities in the left coronary artery. Eight deaths, two non-fatal myocardial infarctions occurred, and 13 revascularizations were performed. With a ROC analysis, a coronary flow velocity &gt;110 cm/s was the best predictor for risk of death (area under curve 0.84 [95% CI 0.74–0.92]; sensitivity 75%; specificity 88%). Only the maximal velocity in proximal left-sided coronary arteries was independently associated with death (HR 1.03, 95% CI 1.01; 1.05; p &lt; 0.002), or death/MI (HR 1.03, 95% CI 1.01; 1.04; p &lt; 0.0001). The cut-off value of 66 cm/s was a predictor of all MACE (area under curve 0.87 [95% CI 0.77–0.94]; sensitivity 80%; specificity 86%). Any causes of death or MI occurred more frequently in patients with velocities of &gt;66 cm/s (27% vs. 2%; p &lt; 0.002). The rates of MACE were 58.0% vs. 2%; p &lt; 0.0000001, respectively. Conclusion The analysis of coronary flow in the left coronary artery during echocardiography can be used as a predictor of outcomes in elderly patients. Maximal velocities in proximal left-sided coronary arteries is independently associated with further death or myocardial infarction.

Intraoperative transesophageal assessment of coronary artery flow can predict 5 type myocardial infarction

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
A Zagatina ◽  
M Novikov ◽  
N Zhuravskaya ◽  
V Balakhonov ◽  
S Efremov ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Cardiac Surgery ◽  
Coronary Artery ◽  
Flow Velocity ◽  
Coronary Flow ◽  
Index Number ◽  
Left Main ◽  
Coronary Flow Velocity ◽  
Before And After ◽  
Flow Velocities

Abstract Background Stenosis of a coronary artery results in an increase in flow velocity in the pathologic segment. Effective grafting should decrease the stenotic native coronary velocity according to hemodynamic law. The range of decreased velocity before and after cardiac surgery can hypothetically reflect the effectiveness of a graft. The aim of the study is to determine if measuring coronary flow velocity changes during coronary artery bypass grafting (CABG) can predict intraoperative myocardial infarction. Methods One hundred sixty-six (166) consecutive patients (121 men, 64±9 years old) referred for cardiac surgery, were prospectively included in the study. A standard basic perioperative transesophageal echocardiography (TEE) examination was performed with additional scans of the left main, left anterior descending (LAD), and circumflex (LCx) arteries' proximal segments. Measurements of coronary flow velocities were performed before and after grafting in the same sites of the arteries. The maximal value of cardiac troponin I (cTnI) after CABG and the additive criteria were accounted for in the analysis as it is described in the expert consensus document for Type 5 myocardial infarction (MI) definition. Results One hundred sixty-three patients (98%) had arterial hypertension, 28 patients (17%) had diabetes mellitus, 35 patients (21%) were currently smokers. The feasibility of coronary flow assessment during cardiac operations was 95%. Before grafting, the mean velocity in the left main artery was 91±49 cm/s, in LAD 101±35 cm/s, and in LCx 117±49 cm/s. There was a significant correlation between changes in coronary flow velocities during operation and the value of cTnI (R=0.34, p&lt;0.0001). Ten patients met the criteria for Type 5 MI. There were no differences in age, body mass index, number of coronary arteries with stenoses, frequency of prior MI, ejection fraction or coronary flow velocity before surgery in patients with and without Type 5 MI. The group of patients with Type 5 MI had an increase in native artery velocities during surgery in comparison with patients without MI, who had a significant decrease in coronary flow velocity after grafting (30±48 vs. −10±30 cm/s; p&lt;0.0006). Increases in native coronary velocities greater than 3 cm/s predicted Type 5 MI with 81% accuracy (sensitivity 88%, specificity 70%). Conclusion Coronary flow velocity assessment during cardiac surgery could predict an elevation of cardiac troponins and Type 5 MI. Funding Acknowledgement Type of funding source: None

Impact on Diabetes Mellitus on the Epicardial Coronary Flow Velocity Assessed by the Thrombolysis in Myocardial Infarction Frame Count

Angiology ◽  
2008 ◽  
Vol 60 (4) ◽  
pp. 431-440 ◽  
Author(s):  
Ahmet Soylu ◽  
Kurtulus Ozdemir ◽  
Mehmet Akif Duzenli ◽  
Mehmet Yazici ◽  
Mehmet Tokac
Keyword(s):  
Diabetes Mellitus ◽  
Myocardial Infarction ◽  
Type 2 Diabetes ◽  
Type 2 Diabetes Mellitus ◽  
Flow Velocity ◽  
Coronary Arteries ◽  
Coronary Flow ◽  
Coronary Flow Velocity ◽  
And Gender

The aim of this study is to evaluate the effect of type 2 diabetes mellitus on epicardial coronary flow velocity assessed by the thrombolysis in myocardial infarction frame count. The thrombolysis in myocardial infarction frame count was measured in 272 coronary arteries from 101 patients with type 2 diabetes mellitus and in 271 coronary arteries from 104 age- and gender-matched patients without type 2 diabetes mellitus referred for coronary angiography. The thrombolysis in myocardial infarction frame count was measured only in normal arteries or in arteries without significant lesion. By both univariate and multivariate analysis, the thrombolysis in myocardial infarction frame count was not related with either type 2 diabetes mellitus or the duration and glycated hemoglobin levels in the patients with type 2 diabetes mellitus. The thrombolysis in myocardial infarction frame count was significantly associated with body surface area, heart rate, and proximal coronary artery diameter. Type 2 diabetes mellitus did not affect epicardial coronary flow velocity assessed by the thrombolysis in myocardial infarction frame count.

Wave speed in human coronary arteries is not influenced by microvascular vasodilation: implications for wave intensity analysis

2014 ◽  
Vol 109 (2) ◽  
Author(s):  
M. Cristina Rolandi ◽  
Kalpa Silva ◽  
Matthew Lumley ◽  
Timothy P. E. Lockie ◽  
Brian Clapp ◽  
...  
Keyword(s):  
Coronary Arteries ◽  
Wave Speed ◽  
Wave Intensity ◽  
Intensity Analysis ◽  
Wave Intensity Analysis
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