T.F. Luescher

2014 ESC/ESA Guidelines on non-cardiac surgery: cardiovascular assessment and management: The Joint Task Force on non-cardiac surgery: cardiovascular assessment and management of the European Society of Cardiology (ESC) and the European Society of Anaesthesiology (ESA).

Authors/Task Force Members: Steen Dalby Kristensen* (Chairperson) (Denmark), Juhani Knuuti* (Chairperson) (Finland), Antti Saraste (Finland), Stefan Anker (Germany), Hans Erik Bøtker (Denmark), Stefan De Hert (Belgium), Ian Ford (UK), Jose Ramón Gonzalez-Juanatey (Spain), Bulent Gorenek (Turkey), Guy Robert Heyndrickx (Belgium), Andreas Hoeft (Germany), Kurt Huber (Austria), Bernard Iung (France), Keld Per Kjeldsen (Denmark), Dan Longrois (France), Thomas F. Lüscher (Switzerland), Luc Pierard (Belgium), Stuart Pocock (UK), Susanna Price (UK), Marco Roffi (Switzerland), Per Anton Sirnes (Norway), Miguel Sousa-Uva (Portugal), Vasilis Voudris (Greece), Christian Funck-Brentano (France).

Low-Dose CT Coronary Angiography in the Step-and-Shoot Mode: Diagnostic Performance

Objective: To investigate the performance of low-dose, dual-source computed tomography (DSCT) coronary angiography in the step-and-shoot (SAS) mode for the diagnosis of significant coronary artery stenoses in comparison with conventional coronary angiography (CCA). Design, setting and patients: Prospective, single-centre study conducted in a referral centre enrolling 120 patients (71 men, mean (SD) age 68 (9) years, mean (SD) body mass index 26.2 (3.2) kg/m2). All study participants underwent DSCT in the SAS mode and CCA within 14 days. Twenty-seven patients were given intravenous β blockers for heart rate reduction before CT. Patients were excluded if a target heart rate ⩽70 bpm could not be achieved by β blockers or when the patients were in non-sinus rhythm. Two blinded readers independently evaluated coronary artery segments for assessability and for the presence of significant (>50%) stenoses. Sensitivity, specificity, negative (NPV) and positive predictive values (PPV) were determined, with CCA being the standard of reference. Radiation dose values were calculated. Results: DSCT coronary angiography in the SAS mode was successfully performed in all 120 patients. Mean (SD) heart rate during scanning was 59 (6) bpm (range 44–69). 1773/1803 coronary segments (98%) were depicted with a diagnostic image quality in 109/120 patients (91%). The overall patient-based sensitivity, specificity, PPV and NPV for the diagnosis of significant stenoses were 100%, 93%, 94% and 100%, respectively. The mean (SD) effective dose of the CT protocol was 2.5 (0.8) mSv (range 1.2–4.4). Conclusions: DSCT coronary angiography in the SAS mode allows, in selected patients with a regular heart rate, the accurate diagnosis of significant coronary stenoses at a low radiation dose.

Dual-source computed tomography coronary angiography: influence of obesity, calcium load, and heart rate on diagnostic accuracy

AIMS To prospectively investigate the diagnostic accuracy of dual-source computed tomography coronary angiography (CTCA) to diagnose coronary stenoses in relation to body mass index (BMI), Agatston score (AS), and heart rate (HR) as compared with catheter coronary angiography (CCA). METHODS AND RESULTS Hundred and fifty consecutive patients (47 female, mean age 62.9 +/- 12.1 years) underwent dual-source CTCA without HR control. Patients were divided into subgroups depending on the median of their BMI (26.0 kg/m2), AS (194), and HR (66 b.p.m.). CCA was considered the standard of reference. Mean BMI was 26.5 +/- 4.2 kg/m2 (range 18.3-39.1 kg/m2), mean AS was 309 +/- 408 (range 0-4387), and HR was 68.5 +/- 12.6 b.p.m. (range 35-102 b.p.m.). Diagnostic image quality was found in 98.1% of all segments (2020/2059). Considering not-evaluative segments at CTCA as false-positive, overall per-patient sensitivity, specificity, positive, and negative predictive value were 96.6%, 86.8%, 82.6%, and 97.5%, respectively. High HR did not deteriorate diagnostic accuracy of CTCA. High BMI and AS were associated with a decrease in per-patient specificity to 84.1% and 77.8%, respectively, while sensitivity and negative predictive value remained high. CONCLUSION Dual-source CTCA provides high diagnostic accuracy irrespective of the HR and serves as a modality to rule-out coronary artery stenoses even in patients with high BMI and AS.

High spatial resolution myocardial perfusion cardiac magnetic resonance for the detection of coronary artery disease

Aims To evaluate the feasibility and diagnostic performance of high spatial resolution myocardial perfusion cardiac magnetic resonance (perfusion-CMR). Methods and results Fifty-four patients underwent adenosine stress perfusion-CMR. An in-plane spatial resolution of 1.4 × 1.4 mm2 was achieved by using 5× k-space and time sensitivity encoding (k–t SENSE). Perfusion was visually graded for 16 left ventricular and two right ventricular (RV) segments on a scale from 0 = normal to 3 = abnormal, yielding a perfusion score of 0–54. Diagnostic accuracy of the perfusion score to detect coronary artery stenosis of >50% on quantitative coronary angiography was determined. Sources and extent of image artefacts were documented. Two studies (4%) were non-diagnostic because of k–t SENSE-related and breathing artefacts. Endocardial dark rim artefacts if present were small (average width 1.6 mm). Analysis by receiver–operating characteristics yielded an area under the curve for detection of coronary stenosis of 0.85 [95% confidence interval (CI) 0.75–0.95] for all patients and 0.82 (95% CI 0.65–0.94) and 0.87 (95% CI 0.75–0.99) for patients with single and multi-vessel disease, respectively. Seventy-four of 102 (72%) RV segments could be analysed. Conclusion High spatial resolution perfusion-CMR is feasible in a clinical population, yields high accuracy to detect single and multi-vessel coronary artery disease, minimizes artefacts and may permit the assessment of RV perfusion.

Magnetic resonance myocardial first-pass perfusion imaging: Parameter optimization for signal response and cardiac coverage

Fast imaging techniques allow monitoring of contrast medium (CM) first‐pass kinetics in a multislice mode. Employing shorter recovery times improves cardiac coverage during first‐pass conditions, but potentially flattens signal response in the myocardium. The aim of this study was therefore to compare in patients with suspected coronary artery disease (CAD) two echo‐planar imaging strategies yielding either extended cardiac coverage or optimized myocardial signal response (protocol A/B, six/four slices; preparation pulse, 60°/90°; delay time, 10/120 msec; readout flip angle, 10°/50°; respectively). In phantoms and myocardium of normal volunteers (N= 10) the CM‐induced signal increase was 2.5–3 times higher with protocol B (P < 0.005) than with protocol A. For the detection of individually diseased coronary arteries (≥1 stenosis with ≥50% diameter reduction on quantitative coronary angiography (QCA)), receiver‐operator characteristics of protocol B (signal upslope in 32 sectors/heart) yielded a sensitivity/specificity of 82%/73%, which was superior to protocol A (P < 0.05, N= 14). For the overall detection of CAD, the sensitivity/specificity of protocol B was 85%/81%. An adequate signal response in the myocardium is crucial for a reliable detection of perfusion deficits during first‐pass conditions. The presented protocol B detects CAD with a sensitivity and specificity similar to scintigraphic techniques. J. Magn. Reson. Imaging 2001;14:556–562.

Combining dual-source computed tomography coronary angiography and calcium scoring: added value for the assessment of coronary artery disease

Objective: To prospectively investigate the diagnostic accuracy of dual-source 64-slice computed tomography coronary angiography (CTCA), calcium scoring (CS) and both methods combined for assessing significant coronary artery stenoses relative to conventional coronary angiography (CCA). Design, setting and patients: Prospective, single-centre study conducted in a referral centre enrolling 74 consecutive patients (24 women; mean age 62 (SD 12) years) from August-October 2006. All study participants underwent CS, CTCA and CCA. Diagnostic accuracy was calculated for CS, CTCA and both methods combined relative to CCA. Not-evaluative segments at computed tomography were considered false positive. Results: CCA identified 139 stenoses in 36 patients. Average heart rate during CTCA was 68 (13) bpm (range 35–102 bpm), and 2% of segments (21/1001) in 11% of patients (8/74) were not evaluative. Considering these as false positives, per-patient sensitivity and specificity was 98% and 87%. When using CS cut-off values of 0 to exclude and ⩾400 to predict stenosis, sensitivity and specificity of CS was 100% and 70%, respectively. Combining CS and CTCA in all patients correctly reclassified five patients, while six were falsely classified as stenotic, all of them correctly classified with CTCA alone. Using CS only in patients with not-evaluative segments correctly reclassified five patients while avoiding misclassifications (sensitivity 98%, specificity 100%). Conclusion: Dual-source CTCA allows the diagnosis of significant stenoses with a high diagnostic accuracy. Selectively combining CS with CTCA in patients with not-evaluative coronary segments improves specificity from 87% to 100% without decreasing the high sensitivity of 98%.

Multicenter Evaluation of Dynamic Three-Dimensional Magnetic Resonance Myocardial Perfusion Imaging for the Detection of Coronary Artery Disease Defined by Fractional Flow Reserve

Background—First-pass myocardial perfusion cardiovascular magnetic resonance (CMR) imaging yields high diagnostic accuracy for the detection of coronary artery disease (CAD). However, standard 2D multislice CMR perfusion techniques provide only limited cardiac coverage, and hence considerable assumptions are required to assess myocardial ischemic burden. The aim of this prospective study was to assess the diagnostic performance of 3D myocardial perfusion CMR to detect functionally relevant CAD with fractional flow reserve (FFR) as a reference standard in a multicenter setting. Methods and Results—A total of 155 patients with suspected CAD listed for coronary angiography with FFR were prospectively enrolled from 5 European centers. 3D perfusion CMR was acquired on 3T MR systems from a single vendor under adenosine stress and at rest. All CMR perfusion analyses were performed in a central laboratory and blinded to all clinical data. One hundred fifty patients were successfully examined (mean age 62.9±10 years, 45 female). The prevalence of CAD defined by FFR (<0.8) was 56.7% (85 of 150 patients). The sensitivity and specificity of 3D perfusion CMR were 84.7% and 90.8% relative to the FFR reference. Comparison to quantitative coronary angiography (≥50%) yielded a prevalence of 65.3%, sensitivity and specificity of 76.5% and 94.2%, respectively. Conclusions—In this multicenter study, 3D myocardial perfusion CMR proved highly diagnostic for the detection of significant CAD as defined by FFR.

Multislice breath-hold spiral magnetic resonance coronary angiography in patients with coronary artery disease: Effect of intravascular contrast medium

First, to apply a breath‐hold multislice 2D spiral magnetic resonance (MR) approach in patients acquiring within 16 heartbeats (acquisition window, 116 msec) a 10‐mm‐thick stack of four slices (resolution, 1.3 × 1.3 mm2); and second, to evaluate the effect of an intravascular Fe‐based contrast medium (CM) on a signal‐to‐noise ratio (SNR) and a contrast‐to‐noise ratio (CNR).

Percutaneous PFO closure with Amplatzer PFO occluder: predictors of residual shunts at 6 months follow-up

OBJECTIVE The objective of this study was to assess predictors of residual shunts after percutaneous patent foramen ovale (PFO) closure with Amplatzer PFO occluder (AGA Medical Corporation, Golden Valley, MN, USA). METHODS All percutaneous PFO closures, using Amplatzer PFO occluder performed at a tertiary center between May 2002 and August 2006, were reviewed. Follow-up, including saline contrast transesophageal echocardiography, was performed in all patients 6 months after the intervention. PATIENTS A total of 135 procedures were performed. Mean age of the patients was 51 years. The indication for PFO closure was an ischemic cerebrovascular event in 92%, paradoxical systemic embolism in 4%, and a diving accident in 4%. Recurrent events prior to PFO closure were noted in 34%. A concomitant atrial septal aneurysm was present in 61%. RESULTS At 6 months follow-up, a residual shunt was detected in 26 patients (19%). Residual shunts were more common in patients with an atrial septal aneurysm (27 vs. 8%, P= .01) and in patients treated with a 35-mm compared with a 25-mm device (39 vs. 15%, P= .01). A concomitant atrial septal aneurysm remained independently associated with residual shunts when controlled for body mass index, gender, age, atrial dimensions, and presence of a Chiari network (odds ratio 4.1, 95% confidence intervals 1.1-15.0). CONCLUSION The presence of atrial septal aneurysms in patients undergoing percutaneous PFO closure with an Amplatzer PFO occluder significantly increases the rate of residual shunts at 6 months follow-up, even if 35-mm devices are used.

Diabetes and Endothelial Dysfunction

Diabetes mellitus is a major risk factor for cardiovascular morbidity and mortality. This condition increases the risk of developing coronary, cerebrovascular and peripheral arterial disease up to 4-fold. Disease severity, as measured by chronic glycaemia, is associated with an increasing frequency of clinical events in each vascular bed. Several trials established that hyperglycaemia is the initiating cause of the diabetic tissue injury that we see in daily clinical practice. This process is modulated by genetic determinants of individual susceptibility and by independent accelerating factors such as hypertension and dyslipidaemia, but glycaemic control remains crucial for prevention of cardiovascular disease. The endothelium plays a key role in control of vascular tone by releasing endothelium-derived autacoids, the most important of which is nitric oxide (NO). Reduced NO bioavailability may represent an important triggering event in the initiation and progression of diabetic disease. The L-arginine/NO pathway is impaired at a number of sites in individuals with diabetes. Endothelial dysfunction is associated with a decrease in either basal or stimulated release of NO or there may be an increased breakdown of NO. In a high glucose setting, vascular cells present an increased generation of reactive oxygen species (ROS), with a consequent reduced bioavailability of NO.In this review we analyse the molecular mechanisms involved in the development and progression of diabetic vascular disease; to this purpose, we examine all the pathways, looking for common up- or down-stream events, the ‘unifying mechanism’, that gives us a more complete picture of diabetic disease. Moreover, we focus on the role of a small adaptor protein, p66shc, involved in the generation and regulation of ROS by mitochondria, referring to our experience in the field. Finally, we look at future perspectives and the promising field of stem cells.