Sternal Anomalies in Asymptomatic Patients after Median Sternotomy and Potential Influencing Factors.

BACKGROUND: We aimed to assess asymptomatic patients who had open-heart surgery with median sternotomy for potential sternal anomalies (SA), their related patient-specific risk factors, and treatment options for the prevention of SA. METHODS: Multiplanar CT scans (CTs) from 131 asymptomatic consecutive patients were analyzed retrospectively. Of these, 83 underwent CABG (63.4%), and 48 had aortic valve (AV) procedures via median sternotomy. Sternal bone healing was analyzed for SA and their exact location. RESULTS: In total, 49 SA were identified in 42 (32.1%) patients; 65% SA were found in the manubrium (n = 32). Five hundred thirty-two wires were implanted (4.2 ± 0.5 wires/patient), out of which 96.1% (n = 511) were figure 8 wires. There was no difference between normal and abnormal sterna with regard to the number of wires used for sternal closure (4.2 ± 0.5 vs. 4.3 ± 0.6, p = ns). The distance between wire placement to the proximal edge of the manubrium in normal and abnormal sterna was comparable (11.2 ± 4.2 vs. 10.9 ± 4.8 mm, p = ns). Patients who underwent CABG had a significantly higher risk for SA (OR = 2.4, p ≤ 0.05, 95% CI [1.2-4.9]). The use of BIMA (OR = 4.4, p ≤ 0.05, 95% CI [1.1-17.9]) and body mass index (BMI) > 31 kg/m2 (OR = 3.4, p ≤ 0.01, 95% CI [1.4-8.3]) significantly increased the risk of SA. CONCLUSION: At least 30% of patients were at an increased risk for SA after receiving a median sternotomy. CABG, use of BIMA, and a BMI > 30 kg/m2 were potential risk factors for the development of SA and warrant close clinical follow-up. Sternal plate fixation, particularly in the manubrium, could be beneficial in such patients.

Long-Term Outcomes after Minimally Invasive Aortic Valve Surgery through Right Anterior Minithoracotomy.

Background Minimally invasive aortic valve surgery (MIAV) through a right anterior minithoracotomy evolved to an accepted procedure with favorable short- and mid-term outcomes, whereas long-term results lack. The aim of this study was to evaluate the long-term outcomes. Materials and Methods All our MIAV patients were included (n = 225). Mean age was 68 ± 12 years, 29% were older than 75 years, and median EuroSCORE was 5 (0-11). Baseline characteristics, inhospital outcomes, and follow-up information about survival, major adverse cardiac and cerebrovascular events (MACCE), and need for reoperation were collected and analyzed. Results In this study, 30-day mortality was 1.3%, and there was no permanent stroke. Mean follow-up time was 69.65 ± 24 months, being the longest so far reported in the literature. At 1 and 7 years, survival was 95.8 and 79%, freedom from MACCE 98.1 and 95.7%, and from reoperation 99.5 and 98.7%, respectively. Conclusion MIAV is safe and feasible with favorable long-term outcomes. In the future, it could serve as benchmark for interventional methods as soon as indications are expanded to young and low-risk patients. Randomized studies are needed to compare the long-term outcomes of these approaches.

Optimizing radiation dose by using advanced modelled iterative reconstruction in high-pitch coronary CT angiography.

PURPOSE: To evaluate the potential of advanced modeled iterative reconstruction (ADMIRE) for optimizing radiation dose of high-pitch coronary CT angiography (CCTA). METHODS: High-pitch 192-slice dual-source CCTA was performed in 25 patients (group 1) according to standard settings (ref. 100 kVp, ref. 270 mAs/rot). Images were reconstructed with filtered back projection (FBP) and ADMIRE (strength levels 1-5). In another 25 patients (group 2), high-pitch CCTA protocol parameters were adapted according to results from group 1 (ref. 160 mAs/rot), and images were reconstructed with ADMIRE level 4. In ten patients of group 1, vessel sharpness using full width at half maximum (FWHM) analysis was determined. Image quality was assessed by two independent, blinded readers. RESULTS: Interobserver agreements for attenuation and noise were excellent (r = 0.88/0.85, p < 0.01). In group 1, ADMIRE level 4 images were most often selected (84%, 21/25) as preferred data set; at this level noise reduction was 40% compared to FBP. Vessel borders showed increasing sharpness (FWHM) at increasing ADMIRE levels (p < 0.05). Image quality in group 2 was similar to that of group 1 at ADMIRE levels 2-3. Radiation dose in group 2 (0.3 ± 0.1 mSv) was significantly lower than in group 1 (0.5 ± 0.3 mSv; p < 0.05). CONCLUSIONS: In a selected population, ADMIRE can be used for optimizing high-pitch CCTA to an effective dose of 0.3 mSv. KEY POINTS: • Advanced modeled IR (ADMIRE) reduces image noise up to 50% as compared to FBP. • Coronary artery vessel borders show an increasing sharpness at higher ADMIRE levels. • High-pitch CCTA with ADMIRE is possible at a radiation dose of 0.3 mSv.

Acute, subacute, and long-term evaluation of a novel endovascular occlusion system in a large animal model.

OBJECTIVES: Endovascular occlusion of blood vessels represents a key component of interventional therapy. While coils are most commonly used, vessel occlusion is generally not achieved immediately and may necessitate a large number of devices. It has been suggested that endovascular plugs may overcome these limitations; however, immediate and durable occlusion remains a challenge with plugs as well. This study evaluates a newly designed endovascular occlusion system (EOS) METHODS: The EOS combines a nitinol coil with an impermeable membranous cap made of expanded polytetrafluoroethylene. The coil offers sufficient radial force to expand the membrane and minimize post-deployment migration. Fifteen test devices were deployed in the iliac (external and internal) and femoral arteries of five miniature swine, while two commercially available devices (platinum coils and a vascular plug) were used as controls in one miniswine. Angiography was performed 1, 5, and 10 minutes after device implantation. Follow-up angiography was obtained either on day 29 or day 61, prior to devices harvesting for histological evaluation and biocompatibility assessment. RESULTS: No clinical complications were observed in the animals throughout the study course. All test devices were deployed as intended, and produced complete and immediate vessel-occlusion. No recanalization or acute migration was observed within 10 minutes of deployment, whereas five test devices had migrated between 5 and 15 mm at follow-up angiography. Complete and durable vessel-occlusion without any sign of recanalization was observed in all EOS devices during the follow-up period. CONCLUSION: The EOS is a safe and reliable device resulting in immediate and durable vessel occlusion in the peripheral arterial circulation. While no device migration was observed in the pelvic area, it was observed with five test and one control devices in the vicinity of highly mobile articulations, leading to the conclusion that occlusion devices should not be placed within hypermobile areas such as the hip joint.

The Potential Impact of Functional Imaging on Decision Making and Outcome in Patients Undergoing Surgical Revascularization.

OBJECTIVE: Coronary angiography (CA) remains the standard for preoperative planning for surgical revascularization. However, besides anatomical imaging, current guidelines recommend additional functional imaging before a therapy decision is made. We assess the impact of functional imaging on the strategy of coronary artery bypass grafting (CABG) with particular regards on postoperative patency and myocardial perfusion. METHODS: After CA, 55 patients (47 males/8 females; age: 65.1 ± 9.5 years) underwent perfusion cardiovascular magnetic resonance (CMR) and dual-source computed tomography (DSCT) before isolated CABG (n = 31), CABG and concomitant valve surgery (valve + CABG; n = 10) and isolated valve surgery (n = 14; control). DSCT was used for analysis of significant stenosis, CMR for myocardial-perfusion to discriminate between: no ischemia (normal), ischemia, or scar. The results, unknown to the surgeons, were compared with CA and related to the location and number of distal anastomoses. Nineteen CABG patients underwent follow-up CMR and DSCT (FU: 13 ± 3 months) to compare the preop findings with the postop outcomes. RESULTS: Thirty-nine patients either received CABG alone (n = 31) or a combined procedure (n = 10) with a total of 116 distal anastomoses. DSCT was compared with CA regarding accuracy of coronary stenosis and showed 91% sensitivity, 88% specificity, and negative/positive predictive values of 89/90%. In total, 880 myocardial segments (n = 55, 16 segments/patient) were assessed by CMR. In 17% (149/880) of segments ischemia and in 8% (74/880) scar tissue was found. Interestingly, 14% (16/116) of bypass-anastomoses were placed on non-ischemic myocardium and 3% (4/116) on scar tissue. In a subgroup of 19 patients 304 segments were evaluated. Thirty-nine percent (88/304) of all segments showed ischemia preoperatively, while 94% (83/88) of these ischemic segments did not show any ischemia postoperatively. In regard to performed anastomoses, 79% of all grafts (49/62) were optimally placed, whereas 21% (13/62) were either placed into non-ischemic myocardium or scar tissue, including 10% occluded grafts (6/62). CONCLUSION: In the whole cohort analysis, 17% of grafts were placed in regions with either no ischemia or scar tissue. The subgroup analysis revealed that 94% of all ischemic segments were successfully revascularized after CABG. Thus, functional imaging could be a promising tool in preoperative planning of revascularization strategy. Avoidance of extensive and unnecessary grafting could further optimize outcomes after CABG.

Use of extracellular matrix patches in cardiac surgery.

A noncellular xenogeneic extracellular matrix derived from the porcine small intestinal submucosa can be used as a new patch material with potential advantages. We review the literature on the use of this material in cardiac surgery.

A physiological controller for turbodynamic ventricular assist devices based on a measurement of the left ventricular volume.

The current article presents a novel physiological control algorithm for ventricular assist devices (VADs), which is inspired by the preload recruitable stroke work. This controller adapts the hydraulic power output of the VAD to the end-diastolic volume of the left ventricle. We tested this controller on a hybrid mock circulation where the left ventricular volume (LVV) is known, i.e., the problem of measuring the LVV is not addressed in the current article. Experiments were conducted to compare the response of the controller with the physiological and with the pathological circulation, with and without VAD support. A sensitivity analysis was performed to analyze the influence of the controller parameters and the influence of the quality of the LVV signal on the performance of the control algorithm. The results show that the controller induces a response similar to the physiological circulation and effectively prevents over- and underpumping, i.e., ventricular suction and backflow from the aorta to the left ventricle, respectively. The same results are obtained in the case of a disturbed LVV signal. The results presented in the current article motivate the development of a robust, long-term stable sensor to measure the LVV.

Off-pump surgery for the poor ventricle?

Severely decreased ejection-fraction is an established risk-factor for worse outcome after cardiac surgery. We compare outcomes of off-pump coronary artery bypass grafting (OPCAB) and on-pump CABG (ONCABG) in patients with severely compromised EF. From 2004 to 2009, 478 patients with a decreased EF ≤35% underwent myocardial-revascularization. Patients received either OPCAB (n = 256) or ONCABG (n = 222). Propensity score (PS), including 50 preoperative risk-factors, was used to balance characteristics between groups. PS adjusted logistic regression analysis was performed to assess mortality and major adverse cardiac and cerebrovascular events (MACCE). A composite endpoint for major non-cardiac complications such as respiratory failure, renal failure, rethoracotomy was applied. Complete revascularization (CR) was assumed when the number of distal anastomoses was larger than that of diseased vessels. There was no difference for mortality (2.3 vs. 4.1%; PS-adjusted odds ratio (PS-OR) = 1.05; p = 0.93) and MACCE (13.7 vs. 17.6%; PS-OR = 1.22; p = 0.50) including myocardial-infarction (1.4 vs. 4.9%; PS-OR = 0.39; p = 0.26), low cardiac output (2.3 vs. 4.7%; PS-OR = 0.75; p = 0.72) and stroke (2.3 vs. 2.7%; PS-OR = 0.69; p = 0.66). OPCAB patients presented with a trend to less frequent occurrence of the non-cardiac composite (12.1 vs. 22.1%; PS-OR = 0.54; p = 0.059) including renal dysfunction (PAOR = 0.77; 95% CI 0.31-1.9; p = 0.57), bleeding (PAOR = 0.42; 95% CI 0.14-1.20; p = 0.10) and respiratory failure (PAOR = 0.39; 95% CI 0.05-3.29; p = 0.39). The rate of complete revascularization was similar (92.2 vs. 92.8%; PS-OR = 0.75; p = 0.50). OPCAB in patients with severely decreased EF is safe and feasible. It may even benefit these patients in regard to non-cardiac complications and does not come at cost of less complete revascularization.

Intramural aortic abscess mimicking chronic aortic dissection.

A 77-year-old patient was referred for progressive fatigue and dyspnea on exertion. Preoperative imaging evaluations including transthoracic echocardiography and computed tomography were suggestive of a chronic ascending aortic dissection with an intramural hematoma. Intraoperatively, the intramural structure was identified as an abscess cavity.

Routine early postoperative computed tomography angiography after coronary artery bypass surgery: clinical value and management implications.

OBJECTIVES: Computed tomography angiography (CTA) is broadly used for long-term follow-up of graft patency after coronary artery bypass graft surgery (CABG). However, its clinical value in the early postoperative setting has not been established yet. We evaluated the benefit of adding CTA to the routine clinical work-up after CABG on patient management. METHODS: A total of 305 consecutive patients (269 males, median age 68 years) underwent CABG and postoperative CTA with a median of 6 days after surgery. Graft patency and additional imaging findings were assessed and their influence on diagnosis and clinical management was evaluated. RESULTS: Graft occlusion or high-grade stenosis was found in 15% of the patients. Additional findings were reported in 44% of the patients, including pericardial (2%) and pleural effusion (27%), large pneumothorax (11%), pulmonary infection (4%), cardiac or vascular thrombus (2%), pulmonary embolism (2%), sternal dehiscence (1%) and additional incidental findings requiring follow-up (6%). CT findings initiated new diagnostic and/or therapeutic measures in 15% of the patients, 47% of those with diseased grafts and 19% of patients with non-graft-related findings. No adverse events related to CTA were documented. CONCLUSIONS: Early routine postoperative assessment of CABG with CTA reveals both cardiac and non-cardiac findings with a high frequency, affecting clinical management in a substantial proportion of patients.

Delayed enhancement imaging of myocardial viability: low-dose high-pitch CT versus MRI.

OBJECTIVES: To evaluate the accuracy of high-pitch delayed enhancement (DE) CT for the assessment of myocardial viability with MRI as the reference standard. METHODS: Twenty-four patients (mean age 66.9 ± 9.2 years) with coronary artery disease underwent DE imaging with 128-slice dual-source CT (prospective electrocardiography (ECG)-triggering) and MRI at 1.5 T. Two observers assessed DE transmurality per segment, and measured signal intensity (MRI) or attenuation (CT) in infarcted and healthy myocardium and noise in the left ventricular blood pool for calculating contrast-to-noise ratios (CNR). RESULTS: 75/408 (18.4%) segments in 18/24 patients (75.0%) showed DE in MRI, of which 28 segments in 10/24 (41.7%) patients were non-viable (scar tissue transmurality >50%). Sensitivity, specificity and accuracy of CT for diagnosis of non-viability were 60.7%, 96.8% and 94.4% per segment, and 90.0%, 92.9% and 91.7% per patient. CNR was significantly higher in MR (7.4 ± 3.0 vs. 4.6 ± 1.5; p = 0.018), and image noise significantly lower (11.6 ± 5.7 vs.15.0 ± 4.5; p = 0.019). Radiation dose of DECT was 0.89 ± 0.07 mSv. CONCLUSIONS: CTDE imaging in the high-pitch mode enables myocardial viability assessment at a low radiation dose and good accuracy compared with MR, although associated with a lower CNR and higher noise.

High-pitch dual-source CT angiography of the aortic valve-aortic root complex without ECG-synchronization.

PURPOSE: To compare image quality and radiation dose of high-pitch computed tomography angiography(CTA) of the aortic valve-aortic root complex with and without prospective ECG-gating compared to a retrospectively ECG-gated standard-pitch acquisition. MATERIALS AND METHODS: 120 patients (mean age 68±13 years) were examined using a 128-slice dual-source CT system using prospectively ECG-gated high-pitch (group A; n=40), non-ECG-gated high-pitch (group B; n=40) or retrospectively ECG-gated standard-pitch (C; n=40) acquisition techniques. Image quality of the aortic root, valve and ascending aorta including the coronary ostia was assessed by two independent readers. Image noise was measured, radiation dose estimates were calculated. RESULTS: Interobserver agreement was good(κ=0.64-0.78). Image quality was diagnostic in 38/40 patients (group A), 37/40(B) and 38/40(C) with no significant difference in number of patients with diagnostic image quality among all groups (p=0.56). Significantly more patients showed excellent image quality in group A compared to groups B and C (each, p<0.01). Average image noise was significantly different between all groups (p<0.05). Mean radiation dose estimates in groups A and B (each; 2.4±0.3 mSv) were significantly lower compared to group C (17.5±4.4 mSv; p<0.01). CONCLUSION: High-pitch dual-source CTA provides diagnostic image quality of the aortic valve-aortic root complex even without ECG-gating at 86% less radiation dose when compared to a standard-pitch ECG-gated acquisition.

Aneurysm of coronary sinus of Valsalva can rupture anytime!

An aneurysm of the sinus of Valsalva ruptures in about 35% of all cases and only leads to acute symptoms in 25% of all patients. This paper illustrates a case of a patient who was scheduled for an elective operation due to an aneurysm of the right coronary sinus of Valsalva, which ruptured and led to the necessity of an emergency surgery.

The potential value of hybrid positron emission tomography/dual-source computed tomography imaging in coronary bypass surgery.

BACKGROUND: We evaluated how comprehensive assessment of coronary artery lesions and their hemodynamic relevance by means of hybrid positron emission tomography (PET) and computed tomography (CT) imaging would affect decision-making in coronary artery bypass surgery (CABG), compared with using invasive coronary angiography (ICA) alone. METHODS: After undergoing ICA, 27 patients (21 men and 6 women; mean SD age, 66 ± 10 years) planned for cardiac surgery were scheduled for myocardial perfusion stress/rest evaluation with [13N]ammonia PET and CT coronary angiography. Only ICA was available to the surgeon. Postoperatively, the performed CABG was compared with the hypothetical strategy based on hybrid PET/CT findings (regional coronary flow reserve [CFR], myocardial perfusion defects). Procedures included CABG (n = 18) alone, CABG combined with valve replacement (n = 6), and CABG combined with isolated valve replacement (n = 3). A total of 56 bypass grafts (28 venous and 28 arterial) and 66 distal anastomoses were placed. RESULTS: CT evaluation showed 93% concordance (66/71) with ICA regarding significant stenoses, with sensitivity, specificity, positive predictive value, and negative predictive value of 93.1%, 98.7%, 94.4%, and 98.4%, respectively. In the PET scan, 16 patients had 1 ischemic region, and 12 patients had 1 scar region, including 5 patients who presented with mixed conditions (scar and ischemia). One patient had a completely normal myocardium. Compared with the performed surgery, PET/CT fusion evaluation showed that of the performed anastomoses, 48% had documented ischemia (with a CFR <2 in 86%), 38% were nonischemic (although a CFR value <2 was found in 78%), and 14% had scar tissue (fixed perfusion defect). CONCLUSIONS: Although <50% of bypasses were placed to areas with myocardial ischemia, the CFR was low in the majority of nonischemic regions, a finding that may have important prognostic relevance. PET/CT fusion imaging could potentially influence planning for CABG and provide incremental prognostic information.

Dual-step prospective ECG-triggered 128-slice dual-source CT for evaluation of coronary arteries and cardiac function without heart rate control: a technical note.

PURPOSE: To describe prospective ECG-triggered dual-source CT dual-step pulsing (pECG(dual_step)) for evaluation of coronary arteries and cardiac function. METHODS: Fifty-one consecutive patients pre- or post-cardiovascular surgery were examined with adaptive sequential tube current modulated (pECG(dual-step)) 128-slice dual-source CT without heart rate control (main padding window: 40% RR interval >65 bpm/70% RR interval <65 bpm). Image quality of coronary arteries was graded (4-point scale), and cardiac function was evaluated. RESULTS: Mean HR was 68 bpm. Thirty-seven patients were in stable sinus rhythm (SR); 14 had arrhythmia. Image quality of coronary arteries was diagnostic in 804/816 (98%) of segments. The number of non-diagnostic segments was higher in patients with arrhythmia as compared to those in SR (4% vs. 0.5%; p = 0.01), and there were fewer segments with excellent image quality (79% vs. 94%; p < 0.001) and more segments with impaired image quality (p < 0.001 and p = 0.002). Global and regional LV function could be evaluated in 41 (80%) and 47 (92%) patients, and valvular function in 48 (94%). In 11/14 of patients with arrhythmia, the second step switched to full mAs, increasing radiation exposure to 8.6 mAs (p < 0.001). The average radiation dose was 3.8 mSv (range, 1.7-7.9) in patients in SR. CONCLUSION: pECG(dual-step)128-slice DSCT is feasible for the evaluation of coronary arteries and cardiac function without heart rate control in patients in stable sinus rhythm at a low radiation dose.

Low-dose CT coronary angiography for the prediction of myocardial ischaemia.

The purpose of this study was to prospectively determine the accuracy of low-dose computed tomography coronary angiography (CTCA) for the diagnosis of functionally relevant coronary artery disease (CAD) using cardiac magnetic resonance (CMR) as a standard of reference. Forty-one consecutive patients (age 64 +/- 10 years) underwent k-space and time broad-use linear acquisition speed-up technique accelerated CMR (1.5 T) and dual-source CTCA using prospective electrocardiography gating within 1 day. CTCA lesions were analysed and diameter stenoses of more than 50% and more than 75% were compared with CMR findings taken as the reference standard for assessing the functional relevance of CAD. CMR revealed perfusion defects in 21/41 patients (51%). A total of 569 coronary segments were analysed with low-dose CTCA. The image quality of low-dose CTCA was diagnostic in 566/569 segments (99.5%) in 39/41 patients (95%). Low-dose CTCA revealed stenoses of more than 50% in 58/123 coronary arteries (47.2%) in 24/41 patients (59%) and more than 75% stenoses in 46/123 coronary arteries (37.4%) in 23/41 patients (56%). Using a greater than 50% diameter stenosis, low-dose CTCA yielded the following per artery sensitivity, specificity, positive and negative predictive values, and accuracy for the detection of perfusion defects: 89%, 79%, 72%, 92% and 83%, respectively. Low-dose CTCA is reliable for ruling out functionally relevant CAD, but is a poor predictor of myocardial ischaemia.

Cardiac CT for the differentiation of bicuspid and tricuspid aortic valves: comparison with echocardiography and surgery.

OBJECTIVE: The purpose of this study is to evaluate the diagnostic performance of CT, compared with that of echocardiography and surgery, for differentiating between bicuspid and tricuspid aortic valves. MATERIALS AND METHODS: Forty-seven patients with bicuspid valve and 47 patients with tricuspid aortic valve underwent retrospectively ECG-gated dual-source CT and echocardiography. Thirty-four (72%) of the 47 patients with bicuspid aortic valve underwent valve surgery. Two independent blinded observers assessed the CT image quality of the aortic valve during diastole and systole on a 4-point scale, determined which phase allowed the differentiation of valve type, distinguished between tricuspid and bicuspid aortic valves, and assessed for the presence of a raphe. Diagnostic performance of CT was determined using echocardiography and surgery as the reference standard. RESULTS: According to echocardiography and surgery, seven (15%) of the 47 bicuspid aortic valves had no raphe, and 40 (85%) had a raphe. CT image quality was diagnostic (i.e., scores of 1-3) in all 94 patients in both diastole and systole. Among patients with bicuspid aortic valve and no raphe, differentiation between tricuspid and bicuspid aortic valves could be performed in diastole in 100% (7/7) of cases. Among patients with bicuspid aortic valve and raphe, differentiation was possible only in systole in 5% (2/40) of cases and when combining diastole and systole in 95% (38/40) of cases. In three bicuspid aortic valves with raphe, the valve was misclassified by CT as tricuspid aortic valve. Overall sensitivity and specificity of CT for the diagnosis of bicuspid aortic valve were 94% and 100%. CONCLUSION: CT is highly accurate for differentiation between bicuspid and tricuspid aortic valves. For bicuspid aortic valves without raphe, diastolic reconstructions are sufficient, whereas in those with a raphe, additional reconstructions in systole are required.

Combined cardiac CT and MRI for the comprehensive workup of hemodynamically relevant coronary stenoses.

OBJECTIVE: The purpose of our study was to prospectively evaluate the accuracy of a comprehensive assessment of coronary artery disease (CAD) with prospectively ECG-gated coronary CT angiography (CTA) and perfusion-cardiac MRI for the detection of hemodynamically relevant coronary stenoses. SUBJECTS AND METHODS: Forty-seven consecutive patients underwent k-space and time broad-use linear acquisition speed-up technique accelerated perfusion-cardiac MRI at 1.5 T and dual-source coronary CTA. Catheter coronary angiography (CA), coronary CTA, and perfusion-cardiac MRI were all performed within a median time interval of 7.5 days. Detection of hemodynamically relevant stenoses by the combination of coronary CTA plus perfusion-cardiac MRI was compared with the combination of CA plus perfusion-cardiac MRI, the latter serving as the standard of reference. RESULTS: CA identified stenoses in 75 of 141 coronary arteries (53.2%) in 33 of 47 patients (70.2%). Cardiac MRI revealed perfusion defects in 30 of 47 patients (63.8%). Image quality of coronary CTA was diagnostic in 635 of 638 segments (99.5%). Coronary CTA revealed stenoses greater than 50% in 76 of 141 coronary arteries (53.9%) of 33 of 47 patients (70.2%). Sensitivity, specificity, negative and positive predictive value, and accuracy of coronary CTA and perfusion-cardiac MRI versus CA and perfusion-cardiac MRI for the detection of hemodynamically relevant stenoses were 96.7%, 100%, 94.4%, 100%, and 97.9%, respectively. CONCLUSION: The combination of coronary CTA and perfusion-cardiac MRI shows diagnostic performance comparable to that of CA and perfusion-cardiac MRI. Preliminary data suggest that coronary CTA may replace CA in the diagnosis of hemodynamically relevant CAD.

Remodelling of the aortic root in severe tricuspid aortic stenosis: implications for transcatheter aortic valve implantation.

Detailed knowledge of aortic root geometry is a prerequisite to anticipate complications of transcatheter aortic valve (TAV) implantation. We determined coronary ostial locations and aortic root dimensions in patients with aortic stenosis (AS) and compared these values with normal subjects using computed tomography (CT). One hundred consecutive patients with severe tricuspid AS and 100 consecutive patients without valvular pathology (referred to as the controls) undergoing cardiac dual-source CT were included. Distances from the aortic annulus (AA) to the left coronary ostium (LCO), right coronary ostium (RCO), the height of the left coronary sinus (HLS), right coronary sinus (HRS), and aortic root dimensions [diameters of AA, sinus of Valsalva (SV), and sino-tubular junction (STJ)] were measured. LCO and RCO were 14.9 +/- 3.2 mm (8.2-25.9) and 16.8 +/- 3.6 mm (12.0-25.7) in the controls, 15.5 +/- 2.9 mm (8.8-24.3) and 17.3 +/- 3.6 mm (7.3-26.0) in patients with AS. Controls and patients with AS had similar values for LCO (P = 0.18), RCO (P = 0.33) and HLS (P = 0.88), whereas HRS (P < 0.05) was significantly larger in patients with AS. AA (r = 0.55,P < 0.001), SV (r = 0.54,P < 0.001), and STJ (r = 0.52,P < 0.001) significantly correlated with the body surface area in the controls; whereas no correlation was found in patients with AS. Patients with AS had significantly larger AA (P < 0.01) and STJ (P < 0.01) diameters when compared with the controls. In patients with severe tricuspid AS, coronary ostial locations were similar to the controls, but a transverse remodelling of the aortic root was recognized. Owing to the large distribution of ostial locations and the dilatation of the aortic root, CT is recommended before TAV implantation in each patient.

Diagnostic accuracy of high-pitch dual-source CT for the assessment of coronary stenoses: first experience.

OBJECTIVES: The objective was to prospectively investigate the diagnostic accuracy of high-pitch (HP) dual-source computed tomography coronary angiography (CTCA) compared with catheter coronary angiography (CCA) for the diagnosis of significant coronary stenoses. METHODS: Thirty-five patients (seven women; mean age 62 ± 8 years) underwent both CTCA and CCA. CTCA was performed with a second-generation dual-source CT system permitting data acquisition at an HP of 3.4. Patients with heart rates >60 bpm were excluded from study enrolment. All coronary segments were evaluated by two blinded and independent observers with regard to image quality on a four-point scale (1: excellent to 4: non-diagnostic) and for the presence of significant coronary stenoses (defined as diameter narrowing exceeding 50%). CCA served as the standard of reference. Radiation dose values were calculated using the dose-length product. RESULTS: Diagnostic image quality was found in 99% of all segments (455/459). Non-diagnostic image quality occurred in a single patient with a sudden increase in heart rate immediately before and during CTCA. Taking segments with non-evaluative image quality as positive for disease, the sensitivity, specificity and positive and negative predictive values were 94, 96, 80 and 99% per segment and 100, 91, 88 and 100% per patient. The effective radiation dose was on average 0.9 ± 0.1 mSv. CONCLUSION: In patients with heart rates ≤60 bpm, CTCA using the HP mode of the dual-source CT system is associated with high diagnostic accuracy for the assessment of coronary artery stenoses at sub-milli-Sievert doses.