Proximal Right Coronary Artery Stenosis Research Articles

Abstract 15578: A Rare Case of Anomalous Left Main Coronary Artery Origin Presenting as ST Elevation Myocardial Infarction

Background: ST-segment elevation myocardial infarctions (STEMI) are uncommon presentations of coronary artery anomalies and pose challenges in the emergent setting of percutaneous coronary interventions. We describe an extremely rare case of left main coronary artery (LMCA) originating off the right coronary artery (RCA) in a patient who presents with STEMI and was found to have Medina 1,1,1 lesion at the origin of the anomalous (LMCA). Case Presentation: An 81-year old male, with a past medical history significant for aortic stenosis and hyperlipidemia, presents to the emergency room for substernal non-radiating chest pressure. His electrocardiogram showed ST segment elevations in inferior and anterior leads. He was taken emergently to the cardiac cath lab. Coronary angiogram revealed a single right coronary ostium with an anomalous LMCA to mid left anterior descending (LAD) artery via dual insertion within a myocardial bridge. There was severe 90% Medina 1,1,1 bifurcating proximal RCA stenosis and 90% proximal LMCA stenosis. The entire left coronary system was fed by the anomalous LMCA, which was inserted into the mid-LAD in a dual insertion, between which there was a myocardial bridge. Cardiothoracic surgery team was consulted, and decision was made to pursue coronary artery bypass grafting (CABG). An intra-aortic balloon pump was placed via right femoral artery and patient was taken for emergent surgery, where he underwent 3 vessel CABG (left internal mammary artery to LAD, saphenous venous graft to obtuse marginal branch and posterior descending artery). Discussion: A broad spectrum of coronary anomalies have been reported, but their incidence in STEMI is rare. We discuss a very rare anomaly in which the entire left coronary system branches off the RCA, and culprit lesion was found to be a Medina 1,1,1 lesion. We aim to add to the sparce data pool of STEMI management in patients with anomalous coronary arteries.

Assessment of right ventricular function using right ventricular outflow tract-systolic excursion in inferior wall myocardial infarction and angiographic correlation to proximal right coronary artery stenosis

Background There are inadequate studies validating the efficacy of several echocardiographic parameters of right ventricular (RV) function in assessing RV infarction and predicting stenosis of proximal right coronary artery (RCA). Most of them evaluated a single parameter and many lacked angiographic correlations.Aim To evaluate RV systolic function using systolic excursion of right ventricular outflow tract (RVOT-SE) by echocardiography with correlation to stenosis of proximal RCA in patients with first incident of acute inferior wall myocardial infarction.Patients and methods Parasternal short-axis view at the level of the aortic valve was obtained using M-mode echocardiography, and RVOT-SE was defined as the RVOT-SE anterior wall. It was measured in 50 patients who underwent CA after acute Inferior ST elevaion myocardial (STEMI).Results Patients with reduced RV function were identified with tricuspid annular plane systolic excursion (TAPSE) below 16 mm. RVOT-SE optimal cutoff values to predict RV systolic dysfunction was SE=5.4 mm with a sensitivity of 91.7% and specificity of 99.97% (area under the curve=0.935, P=0.00). RVOT-SE prediction of proximal RCA stenosis was with a sensitivity of 91.4% and specificity of 90.2%. The study showed significant positive correlations with RV-fractional area change and TAPSE (P=0.00) and significant negative correlations with tissue Doppler myocardial performance index and pulsed wave myocardial performance index (P=0.00).Conclusion RVOT-SE is a naive and precise method for assessing RV systolic function. This study suggested the use of RVOT-SE as a parameter of RV function paired with other indices such as TAPSE.

Accuracy of Clinical Symptoms, Electrocardiographic and Echocardiographic Parameters for Diagnosis of Significant Proximal Right Coronary Artery Lesion in Acute Inferior Wall Myocardial Infarction

<p> </p><p><strong>Aim</strong>: Tissue Doppler (TDI) systolic annular velocity (S') and myocardial performance index may be useful predictors of proximal right coronary artery (RCA) stenosis as a culprit lesion in Inferior wall myocardial infaection in association with clinical symptoms and ECG changes. </p><p><strong>Methods:</strong> In a prospective study, patients with first episode of acute IWMI underwent early conventional and tissue Doppler echocardiographic assessment (within 24 h) of symptom onset and RV indices ; Tricuspid annular systolic plane excursion(TAPSE), myocardial performance index (MPI) and tissue Doppler velocities from RV free wall were measured. Patients underwent coronary angiogram within one month, our Patients divided into two groups(A,B) according to angiographic findings based on the presence or absence of a significant proximal RCA stenosis.</p><p><strong> Results</strong>: There were 35 patients with first episode of IWMI, group A includes (n 14 patient) and group B includes (n 21patient), There was significant difference between groups in TAPSE (1.28cm vs 1.98 p < 0.001) ,MPI-TDI (0.69±0.12 vs 0.38±0.05 p < 0.001), and in S'velocity from RV free wall ( 0.09m/s±0.02 vs 0.12m/s ±0.02 p < 0.001). It was found that S'<10cm/s is apredictor of proximal RCA lesion with sensitivity of 92.86% and specificity of 85.71%ppv 81.25, npv 94.74 , MPI-TDI>0.55 with a sensitivity of 92.86 % and specificity of 100% ,100% PPV and 95.45% NPv, and TAPSE<16mm (sensitivity93%, specificity100%).</p><p> <strong>Conclusion</strong>; RV indices (S' velocity, MPI-TDI and TAPSE ) are useful in predicting proximal RCA as infarct related artery in IWMI.</p>

Tissue Doppler tricuspid annular motion in acute inferior wall myocardial infarction and infarction related artery

BackgroundPatients with inferior wall myocardial infarction (IWMI) associated with right ventricular (RV) infarction have much higher rates of adverse events. AimTissue Doppler (TDI) systolic annular velocity (S′) and myocardial performance index may be useful predictors of proximal right coronary artery (RCA) stenosis as a culprit lesion in inferior wall myocardial infarction. MethodsIn a prospective study, patients with first episode of acute IWMI underwent early conventional and tissue Doppler echocardiographic assessment (within 24h) of symptom onset and RV indices; Tricuspid annular systolic plane excursion(TAPSE), myocardial performance index (MPI) and tissue Doppler velocities from RV free wall were measured. Patients underwent coronary angiogram within one month and were divided into two groups (A, B) according to angiographic findings based on the presence or absence of significant proximal RCA stenosis. ResultsThere were 35 patients with first episode of IWMI, group A includes (n 14 patients) and group B includes (n 21patients), There was significant difference between groups in TAPSE (1.28cm vs 1.98 p<0.001), MPI–TDI (0.69±0.12 vs 0.38±0.05 p<0.001), and in S′ velocity from RV free wall (0.09m/s±0.02 vs 0.12m/s±0.02 p<0.001). It was found that S′<10cm/s is a predictor of proximal RCA lesion with a sensitivity of 92.86% and a specificity of 85.71%ppv 81.25, npv 94.74, MPI–TDI>0.55 with a sensitivity of 92.86% and a specificity of 100%, 100%ppv and 95.45%npv, and TAPSE<16mm (sensitivity 93%, specificity 100%). ConclusionRV indices (S′ velocity, MPI–TDI and TAPSE) are useful in predicting proximal RCA as infarct related artery in IWMI.

Right ventricular echocardiographic parameters for prediction of proximal right coronary artery lesion in patients with inferior wall myocardial infarction

BackgroundClassifying the location of an occlusion in the culprit artery during ST-elevation myocardial infarction is important for risk stratification to optimize treatment. ObjectivesTo compare the validity of echocardiographic parameters assessing right ventricular (RV) function for the prediction of proximal right coronary artery (RCA) lesion in patients with inferior wall myocardial infarction. MethodsThe study included 76 patients after their first episode of acute inferior myocardial infarction with significant RCA lesion (43 patients with proximal RCA stenosis and 33 patients with distal RCA stenosis). Full echocardiographic examination was done before revascularization, including RV dimension, tricuspid annular plane systolic excursion, and tissue Doppler imaging of RV free wall at the level of the tricuspid annulus and recording the following variables: peak systolic velocity (Sm), peak early diastolic velocity, peak late diastolic velocity, ejection time (ET), isovolumetric relaxation time (IVRT), isovolumetric contraction time (IVCT), and myocardial performance index (MPI), which was calculated as (MPI=IVRT+IVCT/ET). ResultsPatients with proximal RCA showed significantly lower Sm (10.44±2.61cm/s vs. 12.11±2.94cm/s, p=0.013) and shorter ET (224.18±49.96ms vs. 280.90±46.12ms, p=0.001). While IVRT, IVCT, and MPI were significantly higher (95.25±19.22ms vs. 68.48±12.77ms, p=0.001; 81.62±23.59ms vs. 60.90±17.38ms, p=0.001; and 0.82±0.222 vs. 0.47±0.10, p=0.001, respectively) when compared with patients with distal RCA stenosis. Multiple regression analysis including (tricuspid annular plane systolic excursion, Sm, and MPI) showed that the most independent predictors for proximal RCA lesions were MPI (p=0.0001). The receiver operator characteristic curve for MPI showed areas under the curve of 97% and a confidence interval of 93%. A cut-off value of 0.58 for MPI had a sensitivity of 95% and specificity of 97% for the diagnosis proximal RCA. ConclusionsThe most independent predictors for proximal RCA lesion is MPI.

Echocardiographic assessment of right ventricular function in inferior wall myocardial infarction and angiographic correlation to proximal right coronary artery stenosis

Presence of right ventricular (RV) infarction imposes a higher risk of adverse events in inferior wall myocardial infarction (IWMI). In this study, we attempted to correlate various indices of RV function assessed by echocardiography with presence of a proximal right coronary artery (RCA) stenosis in patients with first episode of acute IWMI. In a prospective study, patients with first episode of acute IWMI underwent echocardiographic assessment within 24hof symptom onset and indices of RV function viz. RV fractional area change (RVFAC), tricuspid annular plane systolic excursion (TAPSE), myocardial performance index (MPI) and tissue Doppler velocities from RV free wall were measured. Patients who underwent coronary angiogram (CAG) within one month and they were classified into group 1 and group 2 based on the presence or absence, respectively, of a significant proximal RCA stenosis. There were 90 patients with first episode of IWMI of which 67 patients underwent CAG. There was significant difference between group 1 (n=26) and group 2 (n=41) in TAPSE (13.5±1.3 vs21.3±1.7, p<0.001), MPI by tissue Doppler (0.87±0.1 vs0.55±0.2, p<0.001) and in tissue Doppler systolic velocity from RV free wall (S' 9.8±1.1 vs 15.0±1.5, p<0.001). There was a good interobserver correlation for TAPSE, MPI by TDI, and S' velocity. TAPSE≤16 (sensitivity 93%, specificity 100%), MPI-TDI≥0.69 (sensitivity 94.7%, specificity 93.5%), S≤12.3 (sensitivity 90.3%, specificity 94.3%) were useful in predicting presence of proximal RCA stenosis. RV function indices like TAPSE, MPI-TDI and S' velocity are useful in predicting proximal RCA stenosis in first episode of acute IWMI.

The use of perfusion scintigraphy to differentiate proximal right coronary artery stenosis from distal right coronary artery stenosis in patients with inferior left ventricular ischaemia

The identification of patients with a significant proximal right coronary artery (RCA) is of clinical relevance since it may direct diagnostic and therapeutic strategies. This study was performed to determine parameters of (201)Tl RV perfusion SPECT which can be used to discriminate between proximal and distal RCA stenosis in patients with inferior left ventricular (LV) ischaemia. In addition, feasibility and reproducibility of a new semi-quantitative method for the assessment of RV perfusion were evaluated. Inferior LV ischaemia was due to a single distal RCA stenosis in 10 (group I) and proximal RCA stenosis in 27 patients (group II). Twenty patients with normal (201)Tl myocardial perfusion scintigraphy and low likelihood of cardiovascular disease were used as a reference (group III). RV (201)Tl stress uptake did not differ between the three groups. However, group II showed a significantly higher (201)Tl rest uptake indicating RV redistribution whereas in group I and III tracer washout was shown. Extent and severity of LV inferior ischaemia was not different between groups I and II. RV redistribution has a sensitivity of 0.74, a specificity of 0.80, and an overall agreement of 0.76 for detecting proximal RCA stenosis. The feasibility of the assessment of RV (201)Tl perfusion was 94%. Inter-observer and intra-observer coefficients of variation for RV (201)Tl perfusion assessment were 1.5 and 2.4%, respectively. RV (201)Tl perfusion scintigraphy is feasible and reproducible. RV (201)Tl redistribution can be used to discriminate between proximal and distal RCA stenosis in patients with inferior LV ischaemia.

Determination of right ventricular function by transesophageal echocardiography: impact of proximal right coronary artery stenosis

Study objective To investigate whether transesophageal echocardiography (TEE) can provide accurate information on right ventricular (RV) function in patients with right coronary artery (RCA) stenosis, given that a decrease in blood supply from the RCA may invalidate the use of single 2-D echocardiography imaging plane as a guide to RV function. Design Prospective, nonblinded study. Setting University hospital. Patients 30 adult patients undergoing elective cardiac or vascular procedures. Interventions Patients were classified into two groups according to the presence or absence of the proximal RCA (segment 1 or 2) stenosis. Group A patients had no obstructive lesions in the proximal RCA (n = 15). Group B patients had 75% or greater obstructive lesions in the proximal RCA (n = 15). Measurements and main results After induction of anesthesia, RV function was evaluated by both fast-response thermodilution pulmonary artery catheter and TEE. Transesophageal echocardiography-derived RV fractional area change (FAC) and tricuspid annular plane systolic excursion ratio (TAPSE ratio) were compared with thermodilution-derived RV ejection fraction (EF) using linear regression analysis. Transesophageal echocardiography-derived RV end-diastolic area (EDA) was compared with thermodilution-derived end-diastolic volume (EDV). Both methods showed a good correlation in RV, EDV, and EF in Group A, but no correlations in Group B. Conclusions Transesophageal echocardiography does not provide reliable information on RVEF and EDV when proximal RCA stenosis is present.

Visualisation of exercise-induced ischaemia of the right ventricle by thallium-201 single photon emission computed tomography.

OBJECTIVE: Exercise thallium-201 (201T1) single photon emission computed tomography (SPECT) has been used to detect potential ischaemia in the left ventricular myocardium but not in the right ventricle. The purpose...