Cost-effective diagnostic cardiovascular imaging: when does it provide good value for the money?Otero, Hansel; Rybicki, Frank; Greenberg, Dan; Mitsouras, Dimitrios; Mendoza, Jorge; Neumann, Peter
doi: 10.1007/s10554-010-9634-zpmid: 20446040
To summarize the results of all original cost-utility analyses (CUAs) in diagnostic cardiovascular imaging (CVI) and characterize those technologies by estimates of their cost-effectiveness. We systematically searched the literature for original CVI CUAs published between 2000 and 2008. Studies were classified according to several variables including anatomy of interest (e.g. cerebrovascular, aorta, peripheral) and imaging modality under study (e.g. angiography, ultrasound). The results of each study, expressed as cost of the intervention to number of quality-adjusted life years saved ratio (cost/QALY) were additionally classified as favorable or not using $20,000, $50,000, and $100,000 per QALY thresholds. The distribution of results was assessed with Chi Square or Fisher exact test, as indicated. Sixty-nine percent of all cardiovascular imaging CUAs were published between 2000 and 2008. Thirty-two studies reporting 82 cost/QALY ratios were included in the final sample. The most common vascular areas studied were cerebrovascular (n = 9) and cardiac (n = 8). Sixty-six percent (21/32) of studies focused on sonography, followed by conventional angiography and CT (25%, n = 8, each). Twenty-nine (35.4%), 42 (51.2%), and 53 (64.6%) ratios were favorable at WTP $20,000/QALY, $50,000/QALY, and $100,000/QALY, respectively. Thirty (36.6%) ratios compared one imaging test versus medical or surgical interventions; 26 (31.7%) ratios compared imaging to a different imaging test and another 26 (31.7%) to no intervention. Imaging interventions were more likely (P < 0.01) to be favorable when compared to observation, medical treatment or non-intervention than when compared to a different imaging test at WTP $100,000/QALY. The diagnostic cardiovascular imaging literature has growth substantially. The studies available have, in general, favorable cost-effectiveness profiles with major determinants relating to being compared against observation, medical or no intervention instead of other imaging tests.
Dynamic outflow tract obstruction in congenitally corrected transposition of the great arteriesZurick III, Andrew; Menon, Venu
doi: 10.1007/s10554-010-9588-1pmid: 20191324
Congenitally corrected transposition of the great arteries (CCTGA) is a rare form of congenital heart disease, constituting 0.5% of all congenital heart defects. The incidence of left ventricle (non-systemic ventricle) outflow tract obstruction ranges between 44 and 57%. Herein, we present the case of a 45 year old woman with CCTGA with progressively worsening dyspnea who had been referred for surgical correction of severe systemic ventricle (morphologic right ventricle) atrio-ventricular valve (tricuspid valve) regurgitation. Cardiac magnetic resonance imaging (CMR) and transesophageal imaging (TEE) demonstrated severe systemic ventricle (morphologic right ventricle) contractile dysfunction, as well as dynamic non-systemic ventricle (morphologic left ventricle) outflow tract obstruction due to systolic anterior motion (SAM) of the non-systemic ventricle (morphologic left ventricle) atrio-ventricular valve (mitral valve) with a large membranous ventricular septal aneurysm that protrudes into the outflow tract of the non-systemic ventricle (morphologic left ventricle). Ultimately, our patient was felt to be too high-risk for surgical correction and a course of medical therapy has been pursued.
Velocity vector imaging to quantify left atrial functionValocik, Gabriel; Druzbacká, Ludmila; Valocikova, Ivana; Mitro, Peter
doi: 10.1007/s10554-010-9619-ypmid: 20339918
The aim of our study was to assess the feasibility of a new image analysis, velocity vector imaging (VVI), in the assessment of left atrial volumes (LAV) and left atrial ejection fraction (LAEF). We retrospectively analysed 100 transthoracic echocardiographic findings in 71 men, and 29 women (mean age 57 ± 19.8 years). Two subgroups of patients were defined: (1) with left ventricular (LV) EF > 50%, and (2) LV EF < 50%. For the VVI method of indexed LAV assessment we used the apical four-chamber view. From the displacement of LA endocardial pixels time–volume curves were extracted which provided automatically data regarding indexed maximum LAV (LAVImax), indexed minimum LAV (LAVImin), and LAEF. LAVs and LAEF by 2-dimensional echocardiograhy (2DE) were measured by Simpson’s biplane disc summation method. Comparing LAVImax, LAVImin, and LAEF by VVI versus 2DE in the total study population, we found significant correlations: r = 0.94, P < 0.0001, r = 0.94, P < 0.0001, r = 0.79, P < 0.0001, respectively. In addition, LAVImax ≥ 40 ml/m2 was 94% sensitive and 72% specific, LAVImin ≥ 27 ml/m2 was 90% sensitive and 86% specific, and LAEF < 30% was 80% sensitive and 96% specific for the detection of LV systolic dysfunction. There were highly significant inverse associations of LAVImax and LAVImin to LVEF. LAEF was also significantly related to LV systolic function. When comparing the time required for VVI and 2DE measurements, VVI led to 62% reduction in the measurement time. In conclusion, VVI is a feasible method for the assessment of LAVs and LAEF. It provides close agreement with that measured by conventional 2DE Simpson’s biplane method with significant time saved.