Left ventricular deformation and two-dimensional echocardiography: temporal and other parameter values in normal subjects

Segmental contractility can be assessed quantitatively by analyzing deformation, or strain, and the rate of deformation, or the strain rate. This type of analysis can be performed using either tissue Doppler imaging or, more recently, two-dimensional speckle-tracking echocardiography. The aim of this study was to determine typical parameter values in healthy subjects and their reproducibility. The study involved 105 healthy individuals, including 55 women (52.45%). Their mean age was 38.8 ± 9.5 years (range, 20-59 years). All underwent speckle-tracking echocardiography with velocity vector imaging. Mean values for the strain and strain rate for each segment as well as for the time-to-peak normalized by the length of the cycle (TPN) were obtained. The resulting mean values were: circumferential strain, 22.2 ± 4.81% with a TPN of 0.39 ± 0.06; longitudinal strain, 19.84 ± 4.59% with a TPN of 0.42 ± 0.06; circumferential strain rate, 1.64 ± 0.48 1/s with a TPN of 0.23 ± 0.06; and longitudinal strain rate, 1.3 ± 0.49 1/s with a TPN of 0.21 ± 0.09. Intra- and inter-observer variability were moderate in magnitude.

Cardiovascular scientific production in Spain and in the European and global context (2003-2007)

INTRODUCTION AND OBJECTIVES

The publication of research articles has increased considerably in recent years in all biomedical fields. The present study examines the position of Spanish quality research in cardiology in the European and world context, and its evolution during the 5-year period 2003-2007.

METHODS

Using the Science Citation Index Expanded of Thomson Reuters as data source, we compared Spanish cardiovascular scientific production with that of the rest of countries in the European Union and of the most important countries worldwide, along with relative productivity as per number of inhabitants and Gross Domestic Product, and the number of citations in the journals of the <<Cardiac and Cardiovascular Systems>> area of the Journal Citation Reports (CCS-JCR).

RESULTS

Spain ranks sixth in the European Union and ninth worldwide in scientific production (tenth worldwide if only the journals of the first quartile of the CCS-JCR area are considered). As regards the number of citations received, Spain ranks seventh in the European Union and eleventh worldwide. In terms of relative productivity as per number of inhabitants and Gross Domestic Product, the Spanish ranking is less favorable (positions 15 and 18, respectively).

CONCLUSIONS

The ranking of Spanish cardiovascular research is similar to that of other biomedical fields, though its position is less favorable in relation to certain demographic and economical indicators. In order to maintain adequate investigational levels, it is necessary for the European governments and scientific societies to regard the promotion of high-quality cardiological research as a priority concern.

[Prognostic value of B-type natriuretic peptide in unstable angina and non-ST-elevation myocardial infarction]

BACKGROUND AND OBJECTIVE

The B-type natriuretic peptide (BNP) has recently emerged as a prognostic marker in acute coronary syndromes (ACS). This role is based on results from randomized trials and other high selected population studies. The aim of this study was to determine the prognostic value of BNP in unselected patients with non-ST-elevated-ACS.

PATIENTS AND METHOD

BNP plasma concentrations were measured in 100 consecutive patients admitted in 2007 with non-ST-elevated-ACS, taking as cut-off value 80pg/ml (high BNP levels on 48% of patients).

RESULTS

After one year-of follow-up, 21 major adverse cardiovascular events occurred: 12 ACS, 7 hospitalizations for heart failure and 2 sudden cardiac deaths. No relationship was found between BNP levels and events on follow-up. BNP >80pg/ml was the only independent predictor of heart failure and death. No relationship was found between high levels of BNP and coronary events during the follow-up.

CONCLUSIONS

BNP was an independent predictor of heart failure and mortality in unselected patients with non-ST-elevated-ACS.

Comparison of medium-term outcomes obtained with drug-eluting stents and coronary artery bypass grafts in an unselected population of diabetic patients with multivessel coronary disease. Propensity score analysis

INTRODUCTION AND OBJECTIVES

Since the introduction of drug-eluting stents, the optimum revascularization strategy in diabetic patients with multivessel coronary disease has remained controversial.

METHODS

This study used multivariate logistic regression analysis and propensity score matching to compare results in 270 consecutive diabetic patients (2000-2004) with multivessel disease (> or =2 vessels with a >70% de novo stenosis involving the proximal left anterior descending coronary artery) who underwent either coronary artery bypass grafting (CABG; n=142) or implantation of a drug-eluting stent (DES; i.e. rapamycin or paclitaxel; n=128). The following clinical outcomes (i.e. major adverse cardiac or cerebrovascular events [MACCEs]) were assessed: death, nonfatal myocardial infarction (MI), stroke and repeat revascularization at 2 years.

RESULTS

Patients who received DESs were older (67.5+/-7 years vs. 65.3+/-8 years; P=.05) and more often had a previous MI (49.2% vs. 28.2%; P< .01), but no more often had a depressed left ventricular ejection fraction < or =45% (32.4% vs. 28.1%). Coronary anatomy was more complex in surgical patients (SYNTAX score, 25.9+/-7 vs. 18.5+/-6; P< .001) and the quality of revascularization was better (i.e. anatomically complete revascularization: 52.8% vs. 28.1%; P< .01). The incidence of MACCEs was 18.7% in the CABG group and 21.8% in the DES group (adjusted odds ratio [OR] = 0.93; 95% confidence interval [CI], 0.47-1.86). The composite endpoint of death, MI or stroke occurred in 15.8% undergoing CABG and 12.9% receiving a DES (adjusted OR = 1.19; 95% CI, 0.72-1.88). There was less need for revascularization in CABG patients (4.3% vs. 12.1%; adjusted OR = 0.42; 95% CI, 0.16-1.14; P=.09).

CONCLUSIONS

In an unselected population of diabetic patients with multivessel coronary disease, the principle advantage of CABG was the reduced need for revascularization. There was no difference in the rate of death, MI or stroke.

Closure of perivalvular leaks using an Amplatzer occluder

Reoperation of patients with perivalvular leaks due to heart failure or hemolysis is associated with increased morbidity and mortality. Percutaneous closure using an Amplatzer device offers a promising alternative. We describe our initial experience between 2004 and 2006, during which we used an Amplatzer device in eight patients for the percutaneous closure of perivalvular leaks (four aortic and four mitral). The patients were all symptomatic and had a high surgical risk. Device placement was successful in all patients with mitral leaks and in three with aortic leaks. There were no periprocedural complications. With four of the seven (57%) device placements, there was a significant reduction in the degree of regurgitation and, at 12-month follow-up, only these four patients showed clinical improvements. Of the other three, one required reoperation and two died of non-cardiovascular causes. Percutaneous closure of perivalvular leaks was feasible and safe and can be regarded as a treatment option in patients with a high surgical risk.

[Influence of sex on perioperative outcomes in patients undergoing valve replacement for severe aortic stenosis]

INTRODUCTION AND OBJECTIVES

The influence of sex on the prognosis of patients undergoing aortic valve replacement for severe stenosis is unclear. Nevertheless, a number of studies have regarded sex as an independent risk factor. The aim of this study was to evaluate the influence of sex on perioperative outcomes in patients undergoing valve replacement for severe aortic stenosis.

METHODS

This retrospective study involved 577 consecutive patients who underwent aortic valve replacement surgery for severe aortic stenosis between 1996 and April 2007.

RESULTS

Women (44% of patients) were older than men (70.3+/-7.9 years vs. 66.8+/-9.8 years; P< .001), had a smaller body surface area (1.68+/-0.15 m(2) vs. 1.83+/-0.16 m(2); P< .001), more often had arterial hypertension (73% vs. 49%; P< .001), diabetes mellitus (33.5% vs. 24.5%; P=.001) and ventricular hypertrophy (89.1% vs. 83.1%; P< .001), and less often had coronary artery disease (19.1% vs. 31.8%; P< .001) and severe ventricular dysfunction (7.9% vs. 17.4%; P< .001). Nevertheless, women more often suffered acute myocardial infarction perioperatively (3.9% vs. 0.9%; P=.016), had a low cardiac output in the postoperative period (30.3% vs. 22.3%; P=.016) and experienced greater perioperative mortality (13% vs. 7.4%; P=.019) than men. However, after adjustment for various confounding factors, female sex was not a significant independent risk factor for mortality (odds ratio = 2.40; 95% confidence interval, 0.79-7.26; P=.119).

CONCLUSIONS

Perioperative mortality in women with severe aortic stenosis who underwent valve replacement was high. However, after adjustment for potential confounding factors, particularly body surface area, female sex was not an independent risk factor for mortality.

[Benefits of cardiac resynchronization therapy in patients with atrial fibrillation who have not undergone atrioventricular node ablation]

The aim of this study was to compare the effects of cardiac resynchronization therapy on left ventricular function and reverse remodeling in patients in sinus rhythm with the effects in patients with atrial fibrillation who have not undergone atrioventricular node ablation. Echocardiographic and clinical parameters were evaluated at baseline and after 6 months of cardiac resynchronization therapy in 55 patients: 15 had atrial fibrillation and 40 were in sinus rhythm. Device programming was similar in the 2 groups, as were the reductions in QRS interval and echocardiographic measures of asynchrony observed after implantation. However, although significant improvements in end-systolic volume and ejection fraction were seen in both groups, reverse remodeling was greater in patients in sinus rhythm (reduction in end-systolic volume 30.9%+/-24.6% vs 12.5%+/-18.6%; P=.024), as was the relative increase in ejection fraction (15.4%+/-12.6% vs 5.0%+/-7.2%; P=.010). Cardiac resynchronization therapy in patients with atrial fibrillation who had not undergone atrioventricular node ablation resulted in significant improvements in ejection fraction and reverse remodeling, but these were less than those observed in patients in sinus rhythm.

Baseline glutathione peroxidase activity affects prognosis after acute coronary syndromes

Oxidative stress is associated with atherosclerosis and plaque lesions in experimental in vitro models. Few in vivo studies have examined the association between redox status and the prognosis of acute coronary syndromes.We undertook a prospective, observational study of 137 patients who had been admitted because of an acute coronary syndrome. We determined glutathione peroxidase activity (a marker of systemic antioxidant status) and recorded clinical and angiographic features and cardiovascular events (cardiovascular death, reinfarction, readmission with a new ischemic event, or need for coronary revascularization).The mean age of the patients (78% of whom were men) was 61.7 +/- 10.9 years; 76% were admitted with non-ST-segment-elevation acute coronary syndrome. Left ventricular ejection fraction was normal in 61%. In the 23.4% who experienced cardiovascular events, glutathione peroxidase activity was higher (mean, 2.38 vs 1.76 mU/mg of protein; P < 0.01). Two-year event-free survival was lower in patients whose glutathione peroxidase activity was higher than the 50th percentile (63% vs 82%; P = 0.01). Multivariate analysis showed a direct independent relationship between glutathione peroxidase activity and cardiovascular events (hazard ratio, 3.72; 95% confidence interval, 1.53-9.02; P < 0.01).We conclude that patients who experienced acute coronary syndromes and events during follow-up had higher plasma glutathione peroxidase activity, and that glutathione peroxidase activity was an independent predictor of events during follow-up.

Repercussion of functional mitral regurgitation on reverse remodelling in cardiac resynchronization therapy

AIMS

Cardiac resynchronization therapy (CRT) reduces the degree of functional mitral regurgitation (FMR). However, FMR has also been associated with a lack of clinical response to CRT. We undertook this study to determine whether the presence of FMR influences the reverse remodelling induced by CRT.

METHODS AND RESULTS

We used Doppler echocardiography to assess 20 patients with dilated cardiomyopathy before and 6 months after undergoing CRT. We evaluated the effect of reverse remodelling (reduction > or = 10% in end-systolic volume) according to the presence or absence of important FMR, defined as a regurgitant orifice area (ROA) of > or = 0.20 cm(2). Of the 20 patients (mean age, 64.7 +/- 8.2 years, eight women), 9 had marked FMR (ROA 0.40 +/- 0.12 cm(2)), 6 mild FMR (ROA 0.15 +/- 0.02 cm(2)), and 5 had trivial or no FMR. CRT reduced the presence of mitral regurgitation by 33.3% and induced reverse remodelling in 60% of the patients. A ROA > or = 0.20 cm(2) was associated with a lack of reverse remodelling, despite presenting similar baseline characteristics and a reduction in asynchrony to the other patients. Reverse remodelling was produced in all the other patients, with a significant reduction in end-systolic volume (41.7 +/- 21%; P = 0.003), accompanied by improvement in the ejection fraction (P = 0.003) and myocardial performance index (P = 0.027).

CONCLUSION

CRT improved FMR, although the baseline presence of important mitral regurgitation, with a ROA > or = 0.20 cm(2), in patients undergoing CRT was associated with a lack of response in reverse remodelling.

Influence of high homocysteine and low folate plasmatic levels in medium-term prognosis after acute coronary syndromes

BACKGROUND

To test prospectively whether moderate hyperhomocysteinemia and low folate levels could have an influence in the prognosis of 155 patients who presented with an acute coronary syndrome.

METHODS AND RESULTS

After a mean follow-up of 13.4+/-7.4 months, patients with low folate levels had higher percentages of cardiovascular death and major cardiovascular events (33% vs. 5%, p<0.001; 44% vs. 22%, p<0.05) and patients with high homocysteine levels had a higher percentage of major cardiovascular events (31% vs. 14.5%, p<0.03). Kaplan-Meier survival estimates analysis showed that patients with low folate levels had a significantly higher probability of cardiovascular death and lower free-of-events survival (log rank statistic: 21.17, p<0.001 and 6.59, p=0.01). Patients with high homocysteine levels had a lower free-of-events survival (log rank statistic: 4.95, p=0.02). Different survival multivariate analysis model showed that the presence of low folate levels was an independent predictor of cardiovascular death (hazard ratio 8.85, 95% confidence interval 2.6-29.3, p<0.000) and high homocysteine levels was identified as independent predictor of major cardiovascular events (hazard ratio 2.34, 95% confidence interval 1.07-5.12, p<0.03).

CONCLUSIONS

Low folate levels and moderate hyperhomocysteinemia were identified as independent predictors of cardiovascular events in the follow-up.

Beta-blocker therapy for dynamic left ventricular outflow tract obstruction induced by exercise

BACKGROUND

In patients who present with angina, dynamic left ventricular outflow tract obstruction may be responsible of symptoms. The aim of our study was to evaluate the effect of negative inotropic therapy on ventricular physiology and symptoms of patients with dynamic left ventricular outflow tract obstruction induced by exercise in the absence of hypertrophic cardiomyopathy.

METHODS

Seventy eight patients with symptoms of angina, normal exercise SPECT test and normal resting left ventricular systolic function were prospectively analysed with exercise echocardiography. Fifteen of them developed high outflow tract velocities (greater than 2.57 m/s) on effort. After treatment with bisoprolol (mean dose 6.9+/-3.5 mg) in these patients, symptoms and dynamic left ventricular outflow tract obstruction during exercise were re-evaluated.

RESULTS

After negative inotropic therapy, there was a significant reduction of 86.6% in the development of intracavitary gradient (15 to 2 patients). In all patients the left ventricular outflow tract velocities decreased (2.91+/-0.4 m/s to 1.92+/-0.46 m/s, p=0.001). However, the oxygen consumption during exercise was higher (7.3+/-1.7 METs to 8.5+/-1.8 METs, p=0.005), and symptoms improved significantly following therapy, with a reduction in mean NYHA class from 1.9+/-0.5 to 1.0+/-0.0 (p=0.001).

CONCLUSIONS

Negative inotropic therapy may represent a beneficial therapeutic approach in selected patients with dynamic left ventricular outflow tract obstruction induced by exercise and identified during exercise echocardiography.