Preoperative right ventricular dysfunction is a strong predictor of 3 years survival after cardiac surgery.

BACKGROUND: Prognostic value of right ventricular (RV) systolic function is well established in valvular disease, heart failure but has not been evaluated in patients undergoing cardiac surgery. OBJECTIVES: The aim of the present study was to evaluate the prognostic value of preoperative RV dysfunction extensively evaluated on the basis of a large set of echocardiographic parameters [S', RV fractional area change (RVFAC), right myocardial performance index (RMPI), isovolumic acceleration (IVA), RV dP/dt and basal longitudinal strain (BLS)] in a large population of unselected patient awaiting cardiac surgery. METHODS: We prospectively studied 400 consecutive patients referred for cardiac surgery, in a single surgical center. Echocardiography was performed 24 h before surgery and phone interview assessed the survival status (overall and cardiovascular death) 3-years after surgery. RESULTS: Among 400 patients, 271 were male, mean age was 70.3 ± 10.2. At 3-years the overall and cardiovascular mortality was, respectively, 10.5 and 6.8%. The univariate Cox analysis identified all RV function parameters excepted BLS as predictive factors of overall mortality, with the strongest value for RVFAC < 35% (HR 4.8), S' < 10 cm/s (HR 3.8) and IVA < 1.8 m/s2 (HR 3.2) (all P < 0.001). All parameters were associated to cardiovascular mortality. In multivariate analysis, RVFAC, S', dP/dt and IVA were significantly associated to 3-years overall mortality whatever the EuroSCORE. Abnormal RVFAC, S', IVA and BLS were associated to cardiovascular mortality. CONCLUSIONS: The presence of RV dysfunction before cardiac surgery assessed by echo significantly predicts postoperative mortality, and this is true whatever the EuroSCORE level. This result demonstrates the need of adding the assessment of echographic RV function before cardiac surgery.

Echocardiographic assessment of right ventricular systolic function in a population of unselected patients before cardiac surgery: a multiparametric approach is necessary.

BACKGROUND: According to recent USA guidelines, right ventricular (RV) dysfunction can be diagnosed on the basis of a single parameter, such as tricuspid lateral annular systolic velocity (S')<10 cm/s or RV fractional area change (RVFAC)<35%. AIMS: To assess these recommendations in a large unselected cohort of patients awaiting cardiac surgery and evaluate less validated RV function criteria. METHODS: Among the consecutive patients, 413 were prospectively enrolled and underwent comprehensive echocardiography, including S', RVFAC and other RV parameters (right myocardial performance index; acceleration time, isovolumic velocity and isovolumic acceleration [IVA]; RV dP/dt; isovolumic relaxation time; two-dimensional [2D] strain). We defined subgroups of highly probable RV dysfunction (S'<10 cm/s and RVFAC<35%) and highly probable normal RV function (S'≥10 cm/s and RVFAC≥35%) as reference groups. Indices of preload and afterload were also recorded. RESULTS: Of 413 patients, 320 (77.5%) had normal RV function. In 93 patients, S' and/or RVFAC were abnormal; both were abnormal in 39 (42%) patients. Using our reference groups, IVA≤1.8 m/s2 and basal 2D strain≥-17% were of most value in diagnosing RV dysfunction. IVA was least load dependent while basal 2D strain appeared to be afterload and preload dependent. CONCLUSION: In this large population, S' and RVFAC were sometimes discrepant, supporting the need for a multiparametric approach when evaluating RV function. Among seven less validated criteria, IVA and 2D strain had the best diagnostic value. Unlike 2D strain, IVA was not influenced by loading conditions.

Improving stress echocardiography accuracy for detecting left circumflex artery stenosis: a new echocardiographic sign?

BACKGROUND: The accuracy and reproducibility of stress echocardiography (SE) for the detection of coronary artery lesions requires improvement, particularly in the left circumflex artery (LCx). AIMS: To evaluate the feasibility and diagnostic value of a new sign: Rise of the Apical lateral wall and/or Horizontal displacement of the Apex toward the septum ("RA-HA") in apical echocardiographic views. METHODS: Consecutive patients with normal left ventricular function at rest, positive SE and an indication for coronary angiography were included. SEs were analysed blindly by three independent cardiologists: two seniors (S1 and S2) and one junior (J). RESULTS: Of 81 patients, 58 had an exercise SE and 23 had a dobutamine SE. Significant coronary stenosis was found in 59 of 77 patients who underwent coronary angiography (76.6%). Interobserver reproducibility for the presence of RA-HA was very good between S1 and S2 (κ = 0.86), and good between S1 and J (0.67) and S2 and J (0.70). The sensitivity, specificity and positive and negative predictive values of RA-HA for the detection of significant coronary artery stenosis were, respectively, 39-41%, 83-89%, 88-92% and 29-31% for S1/S2; and 29%, 83%, 85% and 26% for J. To predict LCx stenosis (single or multivessel): 67-70%, 89%, 80-81% and 80-82% for S1/S2, respectively, and 50%, 89%, 75% and 74% for J. CONCLUSION: With a short learning curve, RA-HA is easily diagnosed with a very good interobserver reproducibility. It has high specificity and PPV for the detection of a coronary artery stenosis, particularly in the LCx artery, during exercise or dobutamine SE.

Influence of preoperative left ventricular contractile reserve on postoperative ejection fraction in low-gradient aortic stenosis.

BACKGROUND: Dobutamine stress hemodynamics (DSH) has the potential to stratify operative risk in low-gradient aortic stenosis (AS), but little is known about the relation between left ventricle contractile reserve and postoperative left ventricular ejection fraction (LVEF). We sought to assess the value of DSH to predict postoperative improvement in LVEF. METHODS AND RESULTS: Sixty-six consecutive patients with symptomatic severe AS (aortic valve area < or =1 cm2), LVEF < or =40%, and mean pressure gradient < or =40 mm Hg prospectively enrolled in the French multicenter study on low-gradient AS and who survived to aortic valvular replacement (AVR) were included. Preoperative contractile reserve was present in 46 patients (group I; 70%) and absent in 20 patients (group II; 30%). In the overall sample, 58% of patients improved by 2 New York Heart Association (NYHA) classes after AVR. Mean LVEF improved from 29+/-6% to 47+/-11% (P<0.0001). LVEF improved by > or =10 EF units in 38 patients (83%) in group I and in 13 patients (65%) in group II. Mean LVEF improvement was similar in the 2 groups (19+/-10% versus 17+/-11%; P=0.54). On multivariable analysis, multivessel coronary artery disease (P=0.05) and baseline mean transaortic pressure gradient (P=0.01) were related to LVEF improvement, whereas contractile reserve was not. CONCLUSIONS: LVEF increases in the majority of patients with low-gradient AS who survive after AVR. Although the absence of contractile reserve on DSH is related to high operative mortality, it does not predict the absence of LVEF recovery in patients surviving to AVR. These data further support the concept that surgery should not be contraindicated on the basis of absence of contractile reserve alone.

Functional assessment of mitral regurgitation by transthoracic echocardiography using standardized imaging planes diagnostic accuracy and outcome implications.

OBJECTIVES: We sought to assess the value of transthoracic echocardiography (TTE) using standardized imaging planes for the functional analysis of mitral regurgitation (MR) as well as for postoperative outcome implications. BACKGROUND: The feasibility of mitral valve repair is based on functional assessment of MR, mainly by transesophageal echocardiography (TEE). Considering the recent advances in TTE imaging, the incremental value of TEE in this setting needs to be re-examined. METHODS: Consecutive patients (n = 279; 181 men; median age 68 years [quartiles, 61 to 74]) who underwent surgery for MR were enrolled prospectively in two tertiary care centers. The accuracy of TTE (harmonic imaging) versus TEE for functional assessment of MR was evaluated against surgical findings. RESULTS: Valve repair (n = 237 patients, 85%) or replacement (n = 42) was predicted accurately by TTE in 97% of cases; TEE added significant information for only two patients. In the subgroup of degenerative MR (n = 190), agreement with surgical findings for the localization of prolapsed segments was 91% for TTE (kappa, 0.81) and 93% for TEE (kappa, 0.85) without incremental value of TEE (p = 0.40). Patients with single prolapse of the middle posterior scallop (P2) had a better postoperative outcome as compared with patients who had non-P2 lesions (p = 0.008). Furthermore, mitral replacement predicted by TTE was an independent predictor for postoperative long-term mortality (odds ratio 5.7, 95% confidence interval 1.97 to 16.4, p = 0.001). CONCLUSIONS: In experienced hands, functional assessment of MR by TTE can predict accurately valve repairability and has a strong influence on postoperative outcome. Thus, in most cases preoperative TEE is not mandatory, provided intraoperative TEE is performed.

Low-gradient aortic stenosis: operative risk stratification and predictors for long-term outcome: a multicenter study using dobutamine stress hemodynamics.

BACKGROUND: The prognostic value of dobutamine stress hemodynamic data in the setting of low-gradient aortic stenosis has been addressed in small, single-center studies. Larger studies are needed to define the criteria for selecting the patients who will benefit from valve replacement. METHODS AND RESULTS: Six centers prospectively enrolled 136 patients with aortic stenosis (96 men; median age, 72 years [range, 65 to 77 years]; median aortic valve area, 0.7 cm2 [range, 0.6 to 0.8]; mean transaortic gradient, 29 mm Hg [range, 23 to 34 mm Hg]; cardiac index, 2.11 L x min(-1) x m(-2) [range, 1.75 to 2.55 L x min(-1) x m(-2)]). Left ventricular contractile reserve on the dobutamine stress Doppler study was present in 92 patients (group I) and absent in 44 patients (group II). Operative mortality was 5% (3 of 64 patients) in group I compared with 32% (10 of 31 patients) in group II (P=0.0002). Predictors for operative mortality were the lack of contractile reserve (odds ratio, 10.9; 95% confidence interval [CI], 2.6 to 43.4; P=0.001) and a mean transaortic gradient < or =20 mm Hg (odds ratio, 4.7; 95% CI, 1.1 to 21.0; P=0.04). Predictors for long-term survival were valve replacement (hazard ratio, 0.30; 95% CI, 0.17 to 0.53; P=0.001) and left ventricular contractile reserve (hazard ratio, 0.40; 95% CI, 0.23 to 0.69; P=0.001). CONCLUSIONS: In the setting of low-gradient aortic stenosis, surgery seems beneficial for most of the patients with left ventricular contractile reserve. In contrast, the postoperative outcome of patients without reserve is compromised by a high operative mortality. Thus, dobutamine stress Doppler hemodynamics may be factored into the risk-benefit analysis for each patient.