[Correlation between atrial function and functional capacity in highly trained subjects]

AIM

The aim of the study is to show the relationship existing between tissular Doppler imaging (TDI) parameters and functional capacity in highly trained subjects.

METHODS AND PATIENTS

We therefore studied 46 patients including 22 untrained and 24 trained subjects. Each subject had pulsed TDI recording of systolic (S) and diastolic (E and A) longitudinal myocardial velocities in the basal portion of the RV free wall (RV), the septum (sep) and the LV free wall (LV) from apical 4C view. Athletes underwent the same day a cardiopulmonary test during which we measured peak V(O)2 (ml/kg/min) and anaerobic threshold (AT, ml/kg/min) and calculated VE/V(CO)2 slope. We studied differences between echocardiographic parameters in the two groups using Student test. Coefficients of correlations were calculated using the Spearman method.

RESULTS

Differences between two groups concerned Tei index of right (RV) and left ventricle (LV), telediastolic diameter of LV, and A waves on each wall. In athletes RV, sep and LV S waves did not correlate with V(O)2, AT or VE/V(CO)2 RV, sep and LV A waves correlated significantly and negatively with V(O)2, RV and sep A waves negatively with AT, and sep and LV A waves positively with VE/V(CO)2.

CONCLUSION

In athletes, atrial function shows a negative relationship with cardiopulmonary exercise parameters: the lower the proportion of LV filling due to atrial contraction, the better the level of functional capacity. This is probably due to myocardial structure, which allows more efficient early filling in hypertrophic athlete's heart.

[Quantification of right ventricular function by 2D speckle imaging and three dimensional echography. Comparison with MRI]

PURPOSE

The echocardiographic assessment of right ventricular (RV) function requires many different parameters. We studied and compared with magnetic resonance imaging (MRI) two markers of RV function derived from new imaging tools: 2D speckle imaging (2DSI) and three dimensional echography.

METHODS AND RESULTS

Thirty-two patients (19 with RV ejection fraction [RVEF]< or =45%) underwent both complete echocardiography--including standard parameters of RV function (fractional area change [FAC], Tei index, systolic velocity of tricuspid annulus by DTI), 3D full-volume acquisition on RV--and MRI for the evaluation of RV volumes and RVEF. 2DSI was applied to high frame rate cine loops centred on the RV free wall with measurement of peak systolic strain (%) in the basal, median and apical segments of this wall. Strain, especially in RV median and apical segments, is reduced in patients with RVEF less or equal to 45% (median strain: -16.39+/-5.27 vs. -24.74+/-8.00 [p=0.002]; apical strain -13.01+/-6.84 vs. 22.53+/-11.32 [p=0.03]) with a very good correlation with RVEF (r=-0.717, p=0.0001) but also with the usual echographic parameters of RV function, (FAC: r=0.019; Tei: r=0.01; peak systolic velocity: r=0.002). The 3D RVEF is also but poorly correlated with MRI RVEF, (r=0.447, p=0.017). Furthermore, 3D significantly underestimated RV volumes. By multivariate analysis, apical strain (p=0.004) and FAC (p=0.029) were predictive of a decreased RVEF.

CONCLUSION

Apical strain as measured from 2DSI seems a promising parameter in the estimation of RV function. 3D estimation of RVEF is more disappointing because of an important underestimation of RV volumes.

[Non-valvular cardiac devices endocarditis]

The risk of infective endocarditis on pacemaker or ICD is not negligible and has increased in recent years. Several host-related, procedure-related, or device-related risk factors have been recognized. Owing to its potential severity, the possibility of infective endocarditis should be envisaged in patients with repeated pulmonary infections or documented bacteremia and transesophageal echocardiography should then be used. The most common germs causing pacemaker endocarditis are staphylococci. Treatment requires prolonged antibiotic therapy and retrieval of the pacemaker and leads.

[Staphylococcus aureus bacteremia and endocarditis]

The prevalence of Stapylococcus bacteriaemia is increasing worldwide, because of the increasing use of invasive procedures leading to nosocomial infections, but also of a changing way of life (increasing fashion for tattoos or piercing, use of intravenous drugs). Infective endocarditis develops in 10-30% of the cases of staphylococcus bacteriaemia. Staphylococcus aureus endocarditis must be suspected when it develops in the year following heart surgery or implantation of permanent devices. In drug users, it usually involves the tricuspid valve. According to the resistance of the germ to meticillin, antibiotic therapy uses a combination of intravenous penicillin or glycopeptide and an aminoside. Other antibiotics such as fosfomycin, rifampicin, fusidic acid, or clindamycin can be used when aminosides are contra-indicated. The role of newer antibiotic agents, such as daptomycin or linezolide, remains to be established.

Prosthetic valve endocarditis due to coagulase-negative staphylococci: findings from the International Collaboration on Endocarditis Merged Database

Infective endocarditis due to coagulase-negative staphylococci is increasingly recognized as a difficult-to-treat disease associated with poor outcome. The aim of this report is to describe the characteristics and outcome of patients with prosthetic valve endocarditis (PVE) due to coagulase-negative staphylococci versus those of patients with PVE due to Staphylococcus aureus and viridans streptococci. Patients were identified through the International Collaboration on Endocarditis Merged Database. A total of 54 cases of coagulase-negative staphylococci PVE, 58 cases of S. aureus PVE, and 63 cases of viridans-streptococci-related PVE were available for analysis. There was no difference between the three groups with respect to the type of valve involved or the rate of embolization. However, heart failure was encountered more frequently with coagulase-negative staphylococci (54%) than with either S. aureus (33%; p=0.03) or viridans streptococci (32%; p=0.02). In addition, valvular abscesses complicated 39% of infections due to coagulase-negative staphylococci compared with 22% of those due to S. aureus (p=0.06) and 6% of those due to viridans streptococci (p<0.001). Mortality was highest in patients with S. aureus and coagulase-negative staphylococcal endocarditis (47 and 36%, respectively; p=0.22) and was considerably lower in patients with viridans streptococcal endocarditis (p=0.002 compared to patients with coagulase-negative staphylococcal endocarditis). The results of this analysis demonstrate the aggressive nature of coagulase-negative staphylococcal PVE and the substantially greater morbidity and mortality associated with this infection compared to PVE caused by other pathogens.

Enterococcal prosthetic valve infective endocarditis: report of 45 episodes from the International Collaboration on Endocarditis-merged database

Enterococcal prosthetic valve infective endocarditis (PVE) is an incompletely understood disease. In the present study, patients with enterococcal PVE were compared to patients with enterococcal native valve endocarditis (NVE) and other types of PVE to determine differences in basic clinical characteristics and outcomes using a large multicenter, international database of patients with definite endocarditis. Forty-five of 159 (29%) cases of definite enterococcal endocarditis were PVE. Patients with enterococcal PVE were demographically similar to patients with enterococcal NVE but had more intracardiac abscesses (20% vs. 6%; p=0.009), fewer valve vegetations (51% vs. 79%; p<0.001), and fewer cases of new valvular regurgitation (12% vs. 45%; p=0.01). Patients with either enterococcal PVE or NVE were elderly (median age, 73 vs. 69; p=0.06). Rates of in-hospital mortality, surgical intervention, heart failure, peripheral embolization, and stroke were similar in both groups. Patients with enterococcal PVE were also demographically similar to patients with other types of PVE, but mortality may be lower (14% vs. 26%; p=0.08). Notably, 93% of patients with enterococcal PVE came from European centers, as compared with only 79% of patients with enterococcal NVE (p=0.03). Thus, patients with enterococcal PVE have higher rates of myocardial abscess formation and lower rates of new regurgitation compared to patients with enterococcal NVE, but there are no differences between the groups with regard to surgical or mortality rates. In contrast, though patients with enterococcal PVE and patients with other types of PVE share similar characteristics, mortality is higher in the latter group. Importantly, the prevalence of enterococcal PVE was higher in the European centers in this study.

Enterococcal endocarditis: 107 cases from the international collaboration on endocarditis merged database

PURPOSE

To describe clinical features and outcomes of enterococcal left-sided native valve endocarditis and to compare it to endocarditis caused by other pathogens.

SUBJECTS AND METHODS

Patients in the International Collaboration on Endocarditis-Merged Database were included if they had left-sided native valve endocarditis. Demographic characteristics, clinical features, and outcomes were analyzed. Multivariable analysis evaluated enterococcus as a predictor of mortality.

RESULTS

Of 1285 patients with left-sided native valve endocarditis, 107 had enterococcal endocarditis. Enterococcal endocarditis was most frequently seen in elderly men, frequently involved the aortic valve, tended to produce heart failure rather than embolic events, and had relatively low short-term mortality. Compared to patients with non-enterococcal endocarditis, patients with enterococcal endocarditis had similar rates of nosocomial acquisition, heart failure, embolization, surgery, and mortality. Compared to patients with streptococcal endocarditis, patients with enterococcal endocarditis were more likely to be nosocomially acquired (9 of 59 [15%] vs 2 of 400 [1%]; P <.0001) and have heart failure (49 of 107 [46%] vs 234 of 666 [35%]; P = 0.03). Compared to patients with S. aureus endocarditis, patients with enterococcal endocarditis were less likely to embolize (28 of 107 [26%] vs 155 of 314 [49%]; P <.0001) and less likely to die (12 of 107 [11%] vs 83 of 313 [27%]; P = 0.001). Multivariable analysis of all patients with left-sided native valve endocarditis showed that enterococcal endocarditis was associated with lower mortality (odds ratio [OR] 0.49; 95% confidence interval [CI] 0.24 to 0.97).

CONCLUSIONS

Enterococcal native valve endocarditis has a distinctive clinical picture with a good prognosis.

Emergence of endocarditis due to group D streptococci: findings derived from the merged database of the International Collaboration on Endocarditis

The aim of the present study was to compare the epidemiological and clinical characteristics of Streptococcus bovis endocarditis with those of endocarditis caused by oral streptococci, using data obtained from a large international database of uniformly defined cases of infective endocarditis. S. bovis, a well-known cause of infective endocarditis, remains the common name used to designate group D nonenterococcal streptococci. In some countries, the frequency of S. bovis endocarditis has increased significantly in recent years. Data from the International Collaboration on Endocarditis merged database was used to identify the main characteristics of S. bovis endocarditis and compared them with those of infective endocarditis (IE) due to oral streptococci. The database contained 136 cases of S. bovis IE and 511 cases of IE due to oral streptococci. Patients with S. bovis IE were significantly older those with IE due to oral streptococci (63+/-16 vs. 55+/-18 years, P<0.00001). The proportion of streptococcal IE due to S. bovis increased from 10.9% before 1989 to 23.3% after 1989 (P=0.0007) and was 56.7% in France as compared with 9.4% in the rest of Europe and 6.0% in the USA (P<0.00001). Patients with S. bovis IE had more comorbidity and never used intravenous drugs. Complication rates, rates of valve replacement, and mortality rates were similar in the two groups. In conclusion, this study confirmed that S. bovis IE has unique characteristics when compared to endocarditis due to oral streptococci and that it emerged in the 1990s, mainly in France, a finding that is yet unexplained.

[Response to drug therapy of cardiac failure according to gender]

The general profile of women with cardiac failure differs from that of the male population, especially with respect to aetiology and prognosis. Women are often older, have preserved systolic function more often and a higher incidence of risk factors such as hypertension and diabetes. Moreover, global mortality is lower in women. From the therapeutic point of view, women with symptomatic left ventricular dysfunction probably benefit from ACE inhibitors but those with asymptomatic dysfunction have no reduction in mortality with this class of drugs. In addition, treatment with ACE inhibitors is usually interrupted in women because of a higher incidence of secondary effects. The poorer tolerance could be explained by the profile of women with cardiac failure. The large scale multicentre trials with betablockers included very few women. In MERIT-HF, in which there was a large number of women (23%), the female subgroup was the only one in which a benefit in mortality was not demonstrated. However, a retrospective analysis of the data of this subgroup plus a meta-analysis of all trials with betablockers does show improved mortality with this class of drugs in women. In a retrospective study of the DIG study, there seems to be a difference in the effects of digoxin between men and women; the prescription of digoxin is associated with a higher overall mortality in women. Finally, women seem to require diuretics more often than do men. There are many explanations for the differences observed in therapeutic responses between men and women. The role of sex hormones is often evoked, although it has never been clinically proved. The treatment of heart failure in women should take clinical and biological factors specific to women into account and may explain the relative inefficacy of certain forms of treatment.