Non obstructive high-risk plaque but not calcified by coronary CTA, and the G-score predict ischemia.

BACKGROUND: The association of plaque morphology with ischemia in non-obstructive lesions has not been fully eludicated: Calcium density and high-risk plaque features have not been explored. OBJECTIVES: to assess whether high-risk plaque or calcified, and global mixed including non-calcified plaque burden (G-score) by coronary CTA predict ischemia in non-obstructive lesions using non-invasive fractional flow reserve (FFRCT). METHODS: In 106 patients with low-to-intermediate pre-test probability referred to coronary 128-slice dual source CTA, lesion-based and distal FFRCT were computated. The 4 high-risk-plaque criteria: Low-attenuation-plaque, Napkin Ring Sign, positive remodelling and spotty calcification were recorded. Plaque density (HU) and stenosis (MLA,MLD,%area,%diameter stenosis) were quantified. Plaque composition was classified as type 1-4:1 = calcified, 2 = mixed (calcified > non-calcified), 3 = mixed (non-calcified > calcified), 4 = non-calcified, and expressed by the G-score: Z = Sum of type 1-4 per segment. The total plaque segment involvement score (SIS) and the Coronary Calcium Score (Agatston) were calculated. RESULTS: 89 non-obstructive lesions were included. Both lesion-based and distal FFRCT were lower in high-risk-plaque as compared to calcified (0.85 vs 0.93, p < 0.001 and 0.79 vs 0.86, p = 0.002). The prevalence of lesion-based ischemia (FFRCT<0.8) was higher in high-risk-plaque as compared to calcified (25% vs. 2.5%, p = 0.007). Similarly, the rate of distal ischemia (40% vs 17.5%) was higher, respectively. Lower plaque density (HU) indicating higher lipid plaque component (p = 0.024) predicted lesion based FFRCT in low attenuation plaque. For all lesions (n = 89) including calcified (p = 0.003), the correlation enhanced. Positive remodelling and an increasing non-calcified plaque burden (G-score) in relation to calcified were associated with lower FFRCT distal (p = 0.042), but not the SIS and calcium score. CONCLUSION: High-risk-plaque but not calcified, an increasing lipid-necrotic-core component and non-calcified mixed plaque burden (G-score) predict ischemia in non-obstructive lesions (INOCA), while an increasing calcium compactness acts contrary.

Robotically assisted hybrid coronary revascularization: does sequence of intervention matter?

OBJECTIVE: Hybrid coronary revascularization (HCR) is a treatment strategy for the revascularization of multivessel coronary disease that combines the advantages of both minimally invasive surgical techniques and percutaneous coronary intervention (PCI). The optimal sequence by which revascularization should be accomplished has not been determined. We investigated clinical outcomes in a series of patients planned for HCR via robotically assisted totally endoscopic coronary artery bypass (TECAB) and standard PCI based on revascularization sequence. METHODS: A total of 238 patients planned for HCR between 2001 and 2011 were divided into three groups based on treatment sequence: (a) TECAB before PCI, (b) PCI before TECAB, and (c) same-session procedure. Multiple procedural and clinical end points before discharge and up to 2 years after the procedure were compared between the three groups in an intention-to-treat analysis. Demographic features were reviewed to determine baseline differences between each group. RESULTS: Of the 238 patients, 175 (73.5%) underwent TECAB before PCI, 38 patients (16.0%) underwent PCI before TECAB, and 25 (10.5%) underwent a simultaneous revascularization procedure. At baseline, the patients undergoing TECAB before PCI were significantly older. There was a significantly higher incidence of previous myocardial infarction in the PCI-first group (P < 0.001). There was a significant difference in intensive care unit (ICU) length of stay (LOS), with shorter ICU stays in the simultaneous revascularization group (P = 0.031) and shorter hospital LOS in the PCI before TECAB group (P = 0.021). CONCLUSIONS: In conclusion, revascularization sequence did not dramatically impact clinical outcomes in our observational study. The patients undergoing PCI-first and same-session interventions had shorter hospital and ICU LOS compared with the patients undergoing surgery first. Our findings suggest that no revascularization approach is arbitrarily superior and that revascularization sequence should be individualized on the basis of patient presentation and anatomical considerations.

Differences in coronary plaque composition by noninvasive computed tomography angiography in individuals with and without obstructive coronary artery disease.

BACKGROUND: Coronary CT angiography (CCTA) has emerged as a promising non-invasive tool to detect coronary artery disease (CAD) which provides additional information about atherosclerotic plaque composition. We aimed to assess whether differences in plaque composition and plaque burden exist across patients with more and <50% coronary stenosis. METHODS: 1060 patients (58±11 years, 43% females) with an intermediate risk of CAD referred for 64-slice CCTA were studied. Plaque characteristics and burden was analyzed on CCTA images on a per-segment basis (modified 16-segment AHA classification). Plaques types were classified as: calcified (type 1), mixed (predominantly calcified) (type 2), mixed (predominantly non-calcified) (type 3), and non-calcified (type 4). Plaque types in patients with more and <50% stenosis were compared. RESULTS: Overall 373 (35.2%) patients had normal coronaries without evidence of plaque. In the remaining 687 patients, 353 (33%) and 334 (31%) were found to have luminal narrowing of <50% and ≥50% in at-least one coronary artery segment, respectively. Those with ≥50% stenotic CAD demonstrated were more likely to have segments with mixed plaque subtype and less likely to be exclusively non-calcified (relative distribution of 58%, 22%, 10%, 11% for type 1-4 respectively) compared to those with <50% stenosis with (59%, 11%, 6% and 24%, respectively (p=0.006). In multivariable adjustment models, individuals with significant CAD were 5-fold more likely to have increased burden type 1 plaque (≥3 coronary segments) as compared to those with non-obstructive CAD (OR: 5.00, 95% CI: 1.05-23.78). The respective odds ratio (95% CI) for ≥3 coronary segments of type 2, 3 and 4 were 8.73 (3.01-25.23), 4.62 (2.99-0.22-1.55), respectively. CONCLUSIONS: Plaque composition is different according to severity of CAD with a higher mixed plaque and lesser non-calcified plaque burden among those patients with ≥50% stenotic CAD. These findings should stimulate further investigations to assess the prognostic value of coronary plaque subtypes according to their underlying composition.

Evaluation of left ventricular function by 64-multidetector computed tomography in patients undergoing totally endoscopic coronary artery bypass grafting.

OBJECTIVES: The goal of this study was to quantify left ventricular (LV) function with automated 3-dimensional volume segmentation by 64-slice computed tomography (CT) in patients undergoing totally endoscopic coronary artery bypass grafting (CABG). METHODS: We used 64-multidetector CT coronary angiography to examine 63 patients with >70% coronary stenosis who were undergoing totally endoscopic CABG for single-vessel disease (left internal mammary artery to left anterior descending coronary artery) or multivessel disease with the da Vinci robotic surgical device (arrested heart approach). CT measurements were compared with cineventriculography results in 20 patients. RESULTS: The intraobserver variability values for the end-systolic volume (ESV) and the end-diastolic volume (EDV) were excellent (7.2% and 5.2%, respectively). Bland-Altman plots showed good upper and lower limits of agreement (ESV, +9% and -3.3%, respectively; EDV, +17% and -5.9%). Intraobserver variability for the LV ejection fraction (LVEF) was 4.8% with narrow limits of agreement (+7.8%, -2.2%). The mean postprocessing time was 6.5 minutes. Mean values (+/-SD) were 62.7% +/- 12% (range, 23%-86%) for LVEF, 98.4 mL +/- 29 mL for EDV, and 38.3 mL +/- 23 mL for ESV. The LVEF obtained via CT was moderately but significantly correlated with the invasive cineventriculogram (r = 0.51; P = .02; limits of agreement, +18.7% and -18.4%). CONCLUSION: . Through the use of automated LV volume segmentation, 64-slice CT permits fast quantification of LV function in patients with coronary artery disease undergoing totally endoscopic CABG grafting, enabling a comprehensive evaluation of coronary arteries and bypass grafts.

Is there a relation between non-calcifying coronary plaques and acute coronary syndromes? A retrospective study using multislice computed tomography.

OBJECTIVES: The purpose of this study was to assess whether different coronary plaque types as classified by multislice computed tomography (CT) are retrospectively correlated with acute coronary syndromes (ACS) in an unselected study population. METHODS: Sixty-three consecutive patients were examined with 16-slice CT coronary angiography. Coronary plaque types were classified as calcifying type 1, mixed (calcifying > non-calcifying) type 2, mixed (non-calcifying > calcifying) type 3, and non-calcifying type 4. Patients who had an ACS within 17 days were included. All patients underwent invasive coronary angiography. RESULTS: Fifty-eight patients (92%) had coronary plaques evaluated by CT: 18 type 1 (31%), 10 type 2 (17%), 16 type 3 (28%) and 14 type 4 (24%). The presence of a non-calcifying plaque component (types 2-4; 40 of 63 patients, 63%) was correlated with ACS (n = 15; 24%) (p < 0.001). Only type 3 was significantly correlated with ACS (p = 0.01), but plaque types 2 and 4 were not. The diagnostic accuracy of CT for detection of stenosis >50% in proximal segments was: sensitivity 98%, specificity 90%, negative predictive value 97%, positive predictive value 97% per patient. CONCLUSIONS: Mixed calcifying/non-calcifying plaques with a predominantly non-calcifying component (type 3) as classified by multislice CT are retrospectively correlated with ACS.

Diagnostic performance of 64-slice computed tomography in evaluation of coronary artery bypass grafts.

OBJECTIVE: The purpose of this study was to compare the diagnostic accuracy of 64-slice CT with that of invasive angiography in the detection of greater than 50% graft stenosis within 2 weeks of coronary artery bypass grafting and to investigate the clinical value of 64-slice CT. SUBJECTS AND METHODS: Forty-one patients (70 grafts, 46 arterial and 24 venous) underwent 64-slice CT a mean of 2.6 years after minimally invasive or conventional coronary artery bypass surgery. RESULTS: All 70 grafts were assessable, and none of the grafts was excluded from analysis. For the detection of 50-90% graft stenosis, the sensitivity of CT was 75%, the specificity was 95%, the positive predictive value was 67%, and the negative predictive value was 97% (true disease prevalence, 8/70 grafts; 11%). Greater than 50% graft stenosis and occlusion pooled together (prevalence, 14/70; 20%) were detected with a sensitivity of 85%, specificity of 95%, positive predictive value of 80%, and negative predictive value of 96%. Vein graft disease was found in eight (42%) of 19 patent vein grafts (graft age, 15.6 +/- 2.3 years). The disease was nonobstructive in three (16%) of the 19 grafts. The course of the left internal mammary artery was median retrosternal (< 1 cm deep) in 33.3% of conventionally sutured grafts. CONCLUSION: Sixty-four-slice CT angiography can be used for accurate exclusion of greater than 50% graft stenosis, but detection of distal anastomotic stenosis is limited, and the degree of stenosis can be overestimated. The advantages of CT, however, are that it is noninvasive, vein graft disease can be diagnosed at an early stage, and complementary evaluation of extracardiac anatomic features provides useful information before coronary artery bypass grafting is redone.

Hybrid coronary artery revascularization--review and update 2007.

Hybrid coronary revascularization is a combination of minimally invasive coronary artery bypass grafting and percutaneous coronary intervention in patients with multivessel coronary artery disease. The concept is now 10 years old. Implementation was slow, but major developments have taken place. The surgical part of the procedure can be performed in a totally endoscopic fashion instead of by a mini-incision approach and catheter-based intervention includes the use of drug-eluting stents. Whereas during early development staged approaches were taken, simultaneous interventions have become feasible. Hybrid procedures are an attractive option for high-risk patients or for patients who seek a less traumatic revascularization option.

Aortic valve calcification as quantified with multislice computed tomography predicts short-term clinical outcome in patients with asymptomatic aortic stenosis.

BACKGROUND AND AIM OF THE STUDY: Aortic valve calcification may be an independent risk factor for adverse clinical outcome. The study aim was to assess the predictive value of possible risk factors, including the severity of aortic valve calcification as quantified with 16-multislice computed tomography (MSCT) for adverse short-term clinical outcome in patients with asymptomatic, degenerative aortic stenosis (AS). METHODS: Possible risk factors for adverse short-term clinical outcome were prospectively tested in 34 consecutive patients with asymptomatic AS as follows: (i) aortic valve calcium (AVC) score as quantified with MSCT; (ii) echocardiographic parameters--aortic valve area (AVA) calculated with continuity equation, mean and maximal transvalvular pressure gradients, end-diastolic septal wall diameter; and (iii) laboratory tests (brain natriuretic peptide (BNP), C-reactive protein (CRP)). RESULTS: Within 18-24 months of follow up, 11 of 34 patients developed a major adverse clinical outcome. Ten patients suffered from onset of symptoms accompanied by hemodynamic progression, and one patient died from sudden cardiac death. Six of these 10 patients underwent aortic valve replacement, one patient declined surgery, and three patients were not accepted for surgery (one of these died suddenly shortly afterwards). The aortic valve calcium score was the strongest predictor of a major adverse clinical event (p < 0.001) among all parameters assessed (1,928 +/- 789 versus 5,111 +/- 2,409 Agatston units). The plasma level of BNP (p = 0.003), mean transvalvular pressure gradient (p = 0.002) and AVA (p = 0.003) were also risk factors for adverse clinical outcome. CONCLUSION: The AVC score as quantified with MSCT predicted adverse short-term clinical outcome in patients with asymptomatic AS. In patients with severe aortic valve calcification, close follow up examinations are mandatory, and early elective surgery may be considered even in the absence of symptoms. MSCT provides a comprehensive non-invasive imaging approach for risk stratification in patients with asymptomatic AS.

Evaluation of ascending aortic atherosclerosis with 16-multidetector computed tomography is useful before total endoscopic coronary bypass surgery.

BACKGROUND: The purpose of this study was to investigate the assessment of ascending aortic atherosclerosis with 16-multidetector computed tomography (16-MDCT) angiography prior to total endoscopic coronary artery bypass (TECAB) surgery. METHODS: Forty-five patients were examined with electrocardiogram-gated, 16-MDCT angiography. The presence of atherosclerosis at the ascending aorta was graduated as severe (>50% of circumference) or as mild (<50% of circumference). Ascending aortic plaque composition was evaluated based on CT densities expressed as Hounsfield units (HU). TECABs using the Da Vinci telemanipulator were performed either on the arrested heart (n = 39) with an intra-aortic cardiopulmonary bypass (CPB) perfusion device or on the beating heart (n = 6) in patients with severe atherosclerosis. RESULTS: The presence of mild atherosclerosis at the ascending aorta (11/39) was associated with intra-aortic CPB perfusion device-related difficulties such as intra-aortic balloon migration (BM) or balloon rupture (P = .007) in arrested heart TECABs. The CT density of atherosclerotic plaque in patients with BM was mean 58 HU +/- 51 standard deviation (SD), suggesting noncalcifying plaque. In patients without BM, CT density of plaque was mean 526 HU +/- 306 SD corresponding to calcifying plaque (P < .001). Balloon rupture occurred in 2 patients who had calcifying plaque at the ascending aorta. CONCLUSION: Evaluation of ascending aortic atherosclerosis with 16-MDCT angiography is useful prior to TECAB surgery. Even mild atherosclerosis of the ascending aorta is associated with intraoperative difficulties regarding the remote-access perfusion system that is used for arrested heart TECAB surgery.

Diagnostic performance of MDCT for detecting aortic valve regurgitation.

OBJECTIVE: This study evaluates whether ECG-gated 16-MDCT coronary angiography provides a reliable imaging technique for detecting aortic regurgitation (AR). SUBJECTS AND METHODS: We examined 71 patients prospectively with 16-MDCT angiography using retrospective ECG gating during the mid-to-end diastolic phase. A visible central valvular leakage area was considered as a diagnostic criterion for AR. The central valvular leakage area was quantified in patients with positive transthoracic echocardiography (TTE). We compared 16-MDCT to Doppler TTE, the accepted diagnostic standard based on semiquantitative regurgitation jet analysis (grade 0-3+ for mild, moderate, and severe). RESULTS: The overall sensitivity of 16-MDCT for the identification of patients with AR was 81%. The specificity was 91%, the negative predictive value was 70%, and the positive predictive value was 95%. Of the 71 patients, 48 had AR determined by TTE, and 16-MDCT correctly detected AR in 39 of those 48 patients. The sensitivity of 16-MDCT for the detection of patients with moderate and severe AR (grade > or = 1.5+) was 95%, and the specificity was 96% (20 of 21 patients). The sensitivity of 16-MDCT for identification of patients with mild AR (grade < or = 1+) was 70%, and the specificity was 92% (19 of 27 patients). Quantification of the central valvular leakage area was not possible in 50% of cases with AR by TTE because of valve calcifications. CONCLUSION: Sixteen-MDCT coronary angiography provides an accurate, noninvasive imaging technique to detect moderate and severe aortic regurgitation (grade > or = 1.5+). However, severe valve calcifications and mild AR limit its results.

Multislice computed tomography for detection of patients with aortic valve stenosis and quantification of severity.

OBJECTIVES: The purpose of this study was to evaluate whether multislice computed tomography (MSCT) provides a reliable, noninvasive imaging modality for identification of patients with degenerative aortic valve stenosis (AS) by quantifying the aortic valve area (AVA) in comparison to the accepted diagnostic standard transthoracic echocardiography (TTE). BACKGROUND: Management of patients with degenerative AS is based on the severity of disease. The severity of AS in clinical practice is assessed by TTE and classified as mild, moderate, or severe according to the AVA. METHODS: Forty-six patients were examined with contrast-enhanced, electrocardiogram-gated, 16-row MSCT for the evaluation of the diagnostic accuracy. In 30 patients, quantification of the AVA with MSCT was compared to TTE using the continuity equation with Doppler velocity-time integral for calculation of the AVA. RESULTS: Sensitivity of MSCT for the identification of patients with degenerative AS was 100%, and the specificity was 93.7%. Thirty of 46 patients had AS determined by TTE. Quantification of AVA by MSCT (mean AVA = 0.94 cm2) in patients with AS showed a good correlation to TTE (r = 0.89; p < 0.001). Bland-Altman plot illustrated good intermodality agreement between the two methods (limits of agreement, 0.20; 0.29). CONCLUSIONS: Multislice computed tomography may provide an accurate, noninvasive imaging technique for detection of patients with AS and quantification of AVA.

Reduction of soluble P-selectin by statins is inversely correlated with the progression of coronary artery disease.

BACKGROUND: Cell adhesion molecules (CAM) play an important role in the pathogenesis of atherosclerosis by mediating the binding of leukocytes to the endothelium. Soluble CAM isoforms are known to be elevated in the sera of patients suffering from coronary artery disease (CAD). METHODS: We measured the concentrations of soluble intercellular adhesion molecule-1, vascular cell adhesion molecule-1, E-selectin, P-selectin, platelet endothelial cell adhesion molecule-1, and highly sensitive C-reactive protein (hs-CRP) in the blood of 47 CAD patients before and 6 months after starting statin therapy and in 16 untreated CAD patients. The progression of CAD was monitored by calculating the coronary calcium score using electron beam computed tomography. RESULTS: Soluble P-selectin (92+/-11 ng/ml vs. 59 +/- 4 ng/ml, p < 0.0001) and hs-CRP (0.92 +/- 0.14 mg/dl vs. 0.42 +/- 0.11 mg/dl, p < 0.001) decreased significantly in the statin-treated group compared to baseline levels. None of the other proteins studied showed significant changes. In contrast to hs-CRP, the reduction of soluble P-selectin concentrations correlated directly with the lowering of total cholesterol (r(2) = 0.236, p < 0.005) and inversely with the progression of CAD (r(2) = 0.393, p < 0.0001). CONCLUSIONS: Our results suggest P-selectin as an additional marker for the beneficial action of statins in patients with CAD.

High-resolution 16-MDCT evaluation of radial artery for potential use as coronary artery bypass graft: a feasibility study.

OBJECTIVE: The objective of our study was to assess the feasibility of using 16-MDCT angiography for the preoperative assessment of the radial and ulnar arteries and the palmar arches in patients scheduled for radial artery harvesting for coronary artery bypass graft (CABG) surgery. CONCLUSION: Sixteen-MDCT angiography shows promise for the noninvasive preoperative assessment of the radial artery as a CABG donor site.

Hybrid coronary artery revascularization: logistics and program development.

Planning hybrid coronary artery revascularization--a combination of cardiac surgery with percutaneous procedures--requires, at first sight, a very complex logistical setup. Technical and equipment related details should be defined as early as possible in order to have time for training of all OR personnel involved. The most challenging aspect in OR-located hybrid coronary revascularization remains a very close cooperation of cardiac surgeons and interventional cardiologists. This teamwork does include indication findings and subsequent referral of multivessel coronary artery disease patients to hybrid procedures, as well as high individual flexibility of interventionalists and surgeons. The major prerequisite for this cooperation is a mutual acceptance of different revascularization approaches and the intent to combine their most striking advantages. Intraoperative graft angiography during coronary artery bypass grafting (CABG) procedures is one important step toward simultaneous hybrid coronary revascularization procedures. We describe our experience with on table angiography using a mobile C-arm for intraoperative imaging. This fluoroscopy system can in selected cases be used for simultaneous hybrid procedures.