ABSTRACT
BACKGROUND: A certain minimal luminal cross-sectional area has been traditionally used in clinical practice as a cut-off value to determine severity of left main coronary artery (LMCA) stenosis. The severity of stenosis, however, depends on the baseline luminal area (ie, area prior to stenosis), which may vary among individuals. The present study was undertaken to define normal LMCA luminal area using current technology in vivo. METHODS: LMCA luminal area was determined using multislice computed tomography coronary angiography. Eighty-six subjects with normal coronary arteries and calcium score of zero were included in this study. Left ventricular (LV) mass and LV volumes (systolic, diastolic) were also measured. RESULTS: A wide distribution was found in LMCA luminal area, with median value 17.3 mm² and range 8.1-33.9 mm². A relationship was found between log(LMCA luminal area) and log(LV mass) (r=.515; P<.001) and with body surface area (r=.273; P=.01). Significant relationships were also found between LMCA luminal area and LV volumes (systolic, diastolic). In multiple regression analysis, however, the LV mass was the only independent predictor of LMCA luminal area. CONCLUSION: LMCA luminal area varies substantially among individuals with normal coronary arteries and is related to many other factors. The data suggest that the current practice of using a minimal luminal area cut-off when assessing LMCA stenosis may be misleading, and thus available information should be individualized.
Subject(s)
Computed Tomography Angiography/methods , Coronary Angiography/methods , Coronary Stenosis/diagnosis , Coronary Vessels/diagnostic imaging , Multidetector Computed Tomography/methods , Adult , Cross-Sectional Studies , Female , Humans , Male , Reproducibility of Results , Severity of Illness IndexABSTRACT
BACKGROUND: Assessment of the femoral and iliac arteries is essential prior to transcatheter aortic valve replacement (TAVR). It is critical for establishing candidacy for a femoral approach, and can help predict vascular complications. Although computed tomography angiography (CTA) is the standard imaging modality, it has limitations. OBJECTIVE: This study compared CTA with intravascular ultrasound (IVUS) in patients undergoing TAVR evaluation. METHODS: Fifteen patients undergoing pre-TAVR coronary angiography and hemodynamic assessment were recruited. Following coronary angiography, patients underwent distal aortography, bilateral iliac and femoral arteriography, and IVUS assessment. Vascular tortuosity, minimum lumen diameter, and cross-sectional area were obtained and the findings were compared with those obtained from CTA. RESULTS: Correlation between IVUS and CTA was strong for minimum luminal diameter (r=0.62). Concordance was also strong between CTA and invasive iliofemoral angiography for assessment of tortuosity (r=0.75). Utilizing Bland-Altman analysis, vessel diameters obtained by IVUS were consistently greater than those obtained by CTA. The angiography and IVUS strategy was associated with a lower overall mean contrast utilization (29 cc vs 100 cc; P<.001), reduced mean radiation exposure (527 mGy vs 998 mGy; P=.045), and no significant difference in mean test duration (13.3 minutes vs 10 minutes; P=.12). CONCLUSIONS: For femoral and iliac arterial assessment prior to TAVR, IVUS is a viable alternative to CTA with comparable accuracy, and the potential for less contrast use and less radiation exposure. IVUS is also a valuable adjunct to CTA in patients with borderline femoral access diameters or considerable CTA artifacts.
Subject(s)
Aortic Valve Stenosis/surgery , Arterial Occlusive Diseases/diagnosis , Computed Tomography Angiography/methods , Postoperative Complications/prevention & control , Transcatheter Aortic Valve Replacement , Ultrasonography, Interventional/methods , Vascular Malformations/diagnosis , Aged , Aortic Valve Stenosis/complications , Arterial Occlusive Diseases/complications , Comparative Effectiveness Research , Dimensional Measurement Accuracy , Female , Femoral Artery/diagnostic imaging , Humans , Iliac Artery/diagnostic imaging , Male , Preoperative Care/methods , Risk Adjustment/methods , Transcatheter Aortic Valve Replacement/adverse effects , Transcatheter Aortic Valve Replacement/methods , Vascular Malformations/complicationsABSTRACT
Cardiac myxomas are rare primary cardiac tumors that usually present with dyspnea or manifestations of systemic embolization. Coronary steal is a rare phenomenon of unbalanced blood flow that is seen primarily in patients who have undergone coronary artery bypass grafting and have subclavian artery stenosis. We report the case of a 72-year-old woman who presented with fatigue, weakness, and exertional chest heaviness and had abnormal results on a cardiac stress test. The results of coronary angiography showed no obstructive coronary artery disease but revealed a large intracardiac left atrial mass that was supplied by 2 anomalous coronary arteries. The patient underwent successful ligation of the anomalous coronary arteries and resection of the mass, which was histologically an atrial myxoma. The patient's symptoms resolved, and results of a repeat cardiac stress test were normal. To our knowledge, this is the first report of a highly vascularized atrial myxoma that caused coronary steal with objective evidence of ischemia, and with subsequent resolution after resection of the mass and ligation of the anomalous coronary arteries.
