Boudewijn J. Krenning

Statins Are Associated With a Reduced Incidence of Perioperative Mortality in Patients Undergoing Major Noncardiac Vascular Surgery

Background—Patients undergoing major vascular surgery are at increased risk of perioperative mortality due to underlying coronary artery disease. Inhibitors of the 3-hydroxy-3-methylglutaryl coenzyme A (statins) may reduce perioperative mortality through the improvement of lipid profile, but also through the stabilization of coronary plaques on the vascular wall. Methods and Results—To evaluate the association between statin use and perioperative mortality, we performed a case-controlled study among the 2816 patients who underwent major vascular surgery from 1991 to 2000 at the Erasmus Medical Center. Case subjects were all 160 (5.8%) patients who died during the hospital stay after surgery. From the remaining patients, 2 controls were selected for each case and were stratified according to calendar year and type of surgery. For cases and controls, information was obtained regarding statin use before surgery, the presence of cardiac risk factors, and the use of other cardiovascular medication. A vascular complication during the perioperative phase was the primary cause of death in 104 (65%) case subjects. Statin therapy was significantly less common in cases than in controls (8% versus 25%;P <0.001). The adjusted odds ratio for perioperative mortality among statin users as compared with nonusers was 0.22 (95% confidence interval 0.10 to 0.47). Similar results were obtained in subgroups of patients according to the use of cardiovascular therapy and the presence of cardiac risk factors. Conclusion—This case-controlled study provides evidence that statin use reduces perioperative mortality in patients undergoing major vascular surgery.

Contrast superharmonic imaging: A feasibility study

Harmonic imaging provided significant improvement in image quality by taking advantage of the scattered second harmonic (2H) component from contrast bubbles. However, differentiation between contrast and tissue (usually termed contrast-to-tissue ratio, CTR) is sometimes cumbersome and this is mainly due to tissue contamination. We have previously demonstrated, using simulations and in vitro measurements, that CTR increases as a function of the order of the harmonic number. A new contrast imaging method based on the detection of the higher harmonics was developed and termed superharmonic (SH). This technique has been shown to be more sensitive to contrast by increasing the signal from contrast and suppressing that from tissue (high CTR). The purpose of this study was to determine the clinical feasibility and usefulness of SH in patients using a commercially available contrast agent (SonoVue(R)) for quantification of myocardial perfusion. A total of 10 patients with various cardiac diseases were assessed. Apical four-chamber views were acquired using SH in triggered mode before and after contrast injection. The superharmonic was performed with a newly developed probe transmitting at 0.8 MHz with a mechanical index of 0.2. Myocardial perfusion was determined visually and analyzed quantitatively using radiofrequency (RF) processing from different regions of interest. The results showed that, before contrast injection, SH was totally blinded to tissue and no superharmonic components were generated in the image view. After administration of SonoVue(R), myocardial opacification was visualized by SH after contrast entered the myocardium. An increase of more than 15 dB in the myocardial bubbles echo compared to tissue echo was measured. In addition, the technique was used to visualize myocardial perfusion after myocardial septal ablation for hypertrophic cardiomyopathy. The clinical results showed the ability of contrast SH imaging in differentiating low and normal perfusion areas, demonstrating the high sensitivity and specificity of the technique.

Incidence, Pathophysiology, and Treatment of Complications During Dobutamine-Atropine Stress Echocardiography

modality rapidly expanded from diagnosing coronary artery disease (CAD) to risk stratification of patients undergoing vascular surgery; risk stratification of patients with chronic CAD, unstable angina, acute or chronic myocardial infarction (MI), or valvular heart disease; and the assessment of myocardial viability in patients with severe left ventricular (LV) dysfunction. Thus, dobutamine stress has been applied to progressively more complex, older, and higher-risk patients. Additionally, stress protocols became more aggressive, with higher dobutamine doses and the addition of atropine. 3 Although generally regarded as a safe stress modality, serious complications do occur. In this review, we will describe the incidence, pathophysiology, and treatment of complications during dobutamine-atropine stress echocardiography (DASE). Data on incidence of complications were obtained from 26 studies including 400 patients that reported at least the major complications of mortality, acute MI, ventricular fibrillation, and sustained ventricular tachycardia, 4–29 for a total of 55 071 patients (Table 1). In addition, references are given to case reports and studies dealing specifically with a particular complication.

Opposite Patterns of Left Ventricular Remodeling After Coronary Revascularization in Patients With Ischemic Cardiomyopathy: Role of Myocardial Viability

Background—In patients with ischemic cardiomyopathy, left ventricular (LV) remodeling is an important prognostic indicator. The precise relation between viable myocardium, revascularization, and ongoing or reversed remodeling is unknown and was evaluated in the present study. Methods and Results—A total of 100 patients with ischemic cardiomyopathy underwent dobutamine stress echocardiography to assess myocardial viability and LV geometry (volumes and shape). At a mean of 10.2 months and 4.5 years after revascularization, resting echocardiography was repeated to evaluate LV remodeling. Long-term follow-up (mean 5±2 years) data were obtained. According to dobutamine stress echocardiography, 44 patients (44%) were defined as viable (≥4 viable segments) and 56 as nonviable. After revascularization, 40 patients (43%) had ongoing LV remodeling and 53 (57%) did not (in 7 patients who died early after revascularization, postoperative echocardiographic evaluation was not available). On multivariable analysis, the number of viable segments was the only predictor of ongoing LV remodeling (OR 0.60, 95% CI 0.48 to 0.75; P<0.0001). The likelihood of LV remodeling decreased as the number of viable segments increased. During the follow-up, reverse remodeling was present in viable patients, whereas in nonviable patients, LV volumes significantly increased, which indicates ongoing LV remodeling. At follow-up, viable patients also showed a persistent improvement of heart failure symptoms and fewer cardiac events than nonviable patients (P<0.05). Conclusions—In patients with ischemic cardiomyopathy, a substantial amount of viable myocardium prevents ongoing LV remodeling after revascularization and is associated with persistent improvement of symptoms and better outcome.

Guiding and optimization of resynchronization therapy with dynamic three-dimensional echocardiography and segmental volume–time curves: a feasibility study

To assess a new approach for guiding and hemodynamic optimization of resynchronization therapy, using three‐dimensional (3D) transthoracic echocardiography.

Calcium imaging and selective computed tomography angiography in comparison to functional testing for suspected coronary artery disease: the multicentre, randomized CRESCENT trial

AIMS To compare the effectiveness and safety of a cardiac computed tomography (CT) algorithm with functional testing in patients with symptoms suggestive of coronary artery disease (CAD). METHODS AND RESULTS Between April 2011 and July 2013, 350 patients with stable angina, referred to the outpatient clinic of four Dutch hospitals, were prospectively randomized between cardiac CT and functional testing (2 : 1 ratio). The tiered cardiac CT protocol included a calcium scan followed by CT angiography if the Agatston calcium score was between 1 and 400. Patients with test-specific contraindications were not excluded from study participation. By 1 year, fewer patients randomized to cardiac CT reported anginal complaints (P = 0.012). The cumulative radiation dose was slightly higher in the CT group (6.6 ± 8.7 vs. 6.1 ± 9.3 mSv; P < 0.0001). After 1.2 years, event-free survival was 96.7% for patients randomized to CT and 89.8% for patients randomized to functional testing (P = 0.011). After CT, the final diagnosis was established sooner (P < 0.0001), and additional downstream testing was required less frequently (25 vs. 53%, P < 0.0001), resulting in lower cumulative diagnostic costs (€369 vs. €440; P < 0.0001). CONCLUSION For patients with suspected stable CAD, a tiered cardiac CT protocol offers an effective and safe alternative to functional testing. Incorporating the calcium scan into the diagnostic workup was safe and lowered diagnostic expenses and radiation exposure.

Assessment of left ventricular function by three-dimensional echocardiography.

Accurate determination of LV volume, ejection fraction and segmental wall motion abnormalities is important for clinical decision-making and follow-up assessment. Currently, echocardiography is the most common used method to obtain this information. Three-dimensional echocardiography has shown to be an accurate and reproducible method for LV quantitation, mainly by avoiding the use of geometric assumptions. In this review, we describe various methods to acquire a 3D-dataset for LV volume and wall motion analysis, including their advantages and limitations. We provide an overview of studies comparing LV volume and function measurement by various gated and real-time methods of acquisition compared to magnetic resonance imaging. New technical improvements, such as automated endocardial border detection and contrast enhancement, will make accurate on-line assessment with little operator interaction possible in the near future.

Dobutamine stress MRI versus threedimensional contrast echocardiography: It’s all Black and White

Dobutamine stress magnetic resonance imaging is considered the superior stress modality to detect wall motion abnormalities. In this report we demonstrate the strengths of a newly developed stress modality: dobutamine stress contrastenhanced real-time three-dimensional echocardiography. This stress modality may become a competitor of stress magnetic resonance imaging allowing fast acquisition and an unlimited number of left ventricular cross sections. Unfortunately, at the moment adequate imaging with stress realtime three-dimensional echocardiography is only possible in a minority of cardiac patients. (Neth Heart J 2008;16:217-8.)

Prognostic value of dobutamine stress echocardiography in patients with previous coronary revascularisation

Objective: To assess the prognostic value of dobutamine stress echocardiography (DSE) in patients with previous myocardial revascularisation. Design: Prospective study. Setting: Tertiary referral centre in Rotterdam, the Netherlands. Patients: 332 consecutive patients with previous percutaneous or surgical coronary revascularisation underwent DSE. Follow up was successful for 331 (99.7%) patients. Thirty eight patients who underwent early revascularisation (⩽ 3 months) after the test were excluded from analysis. Main outcome measures: Cox proportional hazards regression models were used to identify independent predictors of the composite of cardiac events (cardiac death, non-fatal myocardial infarction, and late revascularisation). Results: During a mean (SD) of 24 (20) months, 37 (13%) patients died and 89 (30%) had at least one cardiac event (21 (7%) cardiac deaths, 11 (4%) non-fatal myocardial infarctions, and 68 (23%) late revascularisations). In multivariate analysis of clinical data, independent predictors of late cardiac events were hypertension (hazard ratio (HR) 1.7, 95% confidence interval (CI) 1.1 to 2.6) and congestive heart failure (HR 2.1, 95% CI 1.3 to 3.2). Reversible wall motion abnormalities (ischaemia) on DSE were incrementally predictive of cardiac events (HR 2.1, 95% CI 1.3 to 3.2). Conclusions: Myocardial ischaemia during DSE is independently predictive of cardiac events among patients with previous myocardial revascularisation, after controlling for clinical data.

Long term outcome in patients with silent versus symptomatic ischaemia during dobutamine stress echocardiography

Objectives: To compare the long term prognosis of patients having silent versus symptomatic ischaemia during dobutamine stress echocardiography (DSE). Design: Observational study. Setting: Tertiary referral centre. Patients: 931 patients who experienced stress induced myocardial ischaemia during DSE. Results: Silent ischaemia was present in 643 of 931 patients (69%). The number of dysfunctional segments at rest (mean (SD) 9.6 (5.1) v 8.8 (5.0), p  =  0.1) and of ischaemic segments (3.5 (2.2) v 3.8 (2.1), p  =  0.2) was comparable in both groups. During a mean (SD) follow up of 5.5 (3.3) years, there were 169 (18%) cardiac deaths and 86 (9%) non-fatal infarctions. Multivariable Cox regression analysis showed age (hazard ratio (HR) 1.1, 95% confidence interval (CI) 1.02 to 1.05), previous myocardial infarction (HR 1.4, 95% CI 1.1 to 2.0), and number of ischaemic segments during the test (HR 2.0, 95% CI 1.0 to 3.7) as independent predictors of cardiac death and myocardial infarction. For every additional ischaemic segment there was a twofold increment in risk of late cardiac events. The annual cardiac death or myocardial infarction rate was 3.0% in patients with symptomatic ischaemia and 4.6% in patients with silent ischaemia (p < 0.01). Silent induced ischaemia was an independent predictor of cardiac death and myocardial infarction (HR 1.7, 95% CI 1.1 to 2.0). During follow up symptomatic patients were treated more often with cardioprotective therapy (p < 0.01) and coronary revascularisation (145 of 288 (50%) v 174 of 643 (27%), p < 0.001). Conclusions: Patients with silent ischaemia had a similar extent of myocardial ischaemia during DSE compared to patients with symptomatic ischaemia but received less cardioprotective treatment and coronary revascularisation and experienced a higher cardiac event rate.