Characterization of mitral valve prolapse with cardiac computed tomography: comparison to echocardiographic and intraoperative findings.

A single imaging modality that can accurately assess both coronary anatomy and mitral valve (MV) anatomy prior to surgery may be desirable. We sought to determine the diagnostic accuracy of cardiac computed tomography (CT) to detect and characterize mitral valve prolapse (MVP) compared to echocardiography. Consecutive patients referred for 'single-source' cardiac CT for investigation prior to non-coronary cardiac sugery were identified. MV anatomy was assessed for MVP and results were compared to echocardiography and to intra-operative visual assessment of the MV. Comparison between the three modalities was performed at the per-patient, per-leaflet and per-scallop levels. A total of 67 consecutive patients that were referred for Cardiac CT prior to non-coronary cardiac surgery and were prospectively recruited into a Cardiac CT registry. Of these, 65 patients underwent cardiac surgery. 63 patients had echocardiography and 32 patients had intra-operative visual assessment of the mitral valve. Compared to echocardiography, cardiac CT had excellent sensitivity (92.6%) and specificity (97.1%) for the detection of any MVP, but had poor sensitivity (68.5%) for the detection of individual prolapsing scallop. Compared to intra-operative visual assessment of the prolapsing scallop, both cardiac CT and echocardiography had low sensitivity (58.1 and 78.1%, respectively). Cardiac CT was able to identify patients with MVP but had difficulty identifying the prolapsed scallops compared to echocardiography. Single-source CT may not be ready for characterization of individual mitral valve scallops.

Rates of downstream invasive coronary angiography and revascularization: computed tomographic coronary angiography vs. Tc-99m single photon emission computed tomography.

AIMS: Computed tomographic coronary angiography (CTA) appears to be a useful modality for the detection of obstructive coronary artery disease (CAD). Recent data suggest that CTA may reduce the frequency of normal invasive coronary angiograms. However, there remains concern that the implementation of CTA could increase referrals to invasive coronary angiography (ICA). To further support the clinical acceptance of CTA, it is important to compare CTA to another accepted modality such as single photon emission computed tomography (SPECT). We followed a cohort of 64-slice CTA patients and a matched cohort of Tc-99m SPECT patients to determine downstream referrals for ICA and revascularization. METHODS AND RESULTS: Consecutive CTA patients (without history of revascularization or cardiac transplantation) were prospectively enrolled and compared with a Tc-99m SPECT cohort (matched for age, gender, and Morise score). Each CTA and SPECT was evaluated for obstructive CAD and patients were followed for downstream ICA and revascularization. Of the 1221 patients in each cohort, 129 (10.6%) CTA patients and 125 (10.2%) SPECT patients were referred to ICA. Of those referred to ICA, obstructive CAD was confirmed in 105 (81.4%) CTA patients and in 88 (70.4%) SPECT patients. Differences in false positive rates were significantly lower in the CTA than the SPECT cohort (9.7 and 25.8%, respectively, P = 0.009). Rates of revascularization were similar in the CTA and SPECT cohorts (6.2 vs. 5.9%, respectively). CONCLUSION: Compared with SPECT, CTA had similar referrals for ICA and revascularization rates but lower false positive rates. Computed tomographic coronary angiography appears to be a viable non-invasive diagnostic modality and does not appear to negatively impact upon ICA resources.