Quantitative assessment of aortic regurgitation by Doppler echocardiography: Usefulness of the comparison of aortic and pulmonary flows.

AIMS: Patients with significant (3+/4+) aortic regurgitation (AR) require careful monitoring or valve surgery. We sought to evaluate the diagnostic performance of aortic and pulmonary flow comparison in identifying patients with significant AR, by echocardiography. METHOD: Two hundred forty-six patients with more than trivial AR were prospectively enrolled from three centers. Aortic regurgitation (AR) severity was assessed by an expert using the currently recommended integrative approach. Aortic and pulmonary flows were independently assessed by another investigator to calculate the regurgitant fraction (RF), the aortic to pulmonary flow ratio (Qao/Qp) and the aortic to pulmonary velocity-time integral (VTIao/VTIp) ratio. The control group consisted of 195 patients without AR. RESULTS: A significant correlation was observed between AR grading and RF (r = .82, P < .0001) and Qao/Qp (r = .81, P < .0001), but the correlation was modest for VTIao/VTIp ratio (r = .63; P < .0001). The accuracy of RF and Qao/Qp ratio to identify patients with significant AR was excellent (0.96 and 0.95, respectively), but was significantly lower for VTIao/VTIp ratio at 0.82. A RF > 40% indicated grade 3 or 4 AR with a sensitivity of 83% and a specificity of 93%. A Qao/Qp ratio > 1.6 indicated grade 3 or 4 AR with a sensitivity of 88% and a specificity of 89%. The VTIao/VTIp ratio was not helpful in identifying patients with significant AR, as a wide overlap was found between 1+/2+ and 3+/4+ patients. CONCLUSION: Regurgitant fraction (RF) and Qao/Qp are helpful in identifying significant AR. The assessment of Doppler aortic/pulmonary flow should be incorporated in the comprehensive evaluation of AR.

[How to detect myocardial ischemia in patients following acute coronary syndrome treated by PCI?] / Quel dépistage de l'ischémie myocardique après angioplastie dans le syndrome coronaire aigu ?

Unstable coronary artery disease is a more aggressive condition than stable coronary artery disease, accounting for the high incidence of major adverse cardiovascular events following acute coronary syndromes (ACS), which includes the need for iterative repeat revascularization. The aim of myocardial ischemia screening in post-ACS patients is to detect this unfavourable evolution (either on initial culprit or non culprit lesions) and to prevent any clinical complication. Although there is no strict recommendation in this particular situation, screening should be based on the use of stress imaging techniques. The optimal timing and frequency for testing will depend on the clinical characteristics of the patients and the coronary revascularization procedure features.

Noninvasive Coronary Flow Reserve Predicts Response to Exercise in Asymptomatic Severe Aortic Stenosis.

BACKGROUND: In patients with asymptomatic aortic stenosis (AS), exercise stress echocardiography (ESE) provides additional prognostic information beyond baseline. The coronary flow velocity reserve (CFVR) is impaired in AS, but its link with exertion is unknown in this setting. The aim of this study was to test the hypothesis that CFVR could predict exercise capacity and abnormal exercise test results in AS. METHODS: Noninvasive CFVR and symptom-limited semisupine ESE were prospectively performed the same day in 43 patients with asymptomatic isolated severe AS (mean age, 68.5 ± 11 years; 26% women; mean aortic valve area, 0.8 ± 0.16 cm2; mean left ventricular ejection fraction, 70 ± 7%). CFVR was performed in the distal part of the left anterior descending coronary artery using intravenous adenosine infusion (140 µg/kg/min over 2 min), and ESE was performed at an initial workload of 25 W with a 20- to 25-W increase at 2-min intervals. An abnormal result on ESE was defined as onset of symptoms at <75% of maximum predicted workload, electrocardiographic ST-segment depression ≥2 mm during exercise, increase of systolic blood pressure < 20 mm Hg or decrease in blood pressure, and complex ventricular arrhythmia. Seventeen patients with isolated severe asymptomatic AS, unable to exercise because of extracardiac conditions, served as a comparative group. RESULTS: Resting, hyperemic left anterior descending coronary artery flow velocity and CFVR (2.45 ± 0.8 vs 2.4 ± 0.8) were similar between the group unable to perform ESE and the ESE group (P = NS for all). Compared with patients with normal results on ESE, those with abnormal results on ESE (n = 22) were older, had higher E/e' ratios, had higher resting left anterior descending coronary artery flow velocities (39 ± 12 vs 31 ± 8 cm/sec), and had lower CFVR (2.01 ± 0.3 vs 2.85 ± 0.7; P < .01 for all). Furthermore, CFVR was significantly correlated with age, changes in transvalvular pressure gradient and left ventricular ejection fraction with exercise, workload (in watts), and exercise duration (P < .05 for all). After adjusting for other variables, CFVR remained independently correlated with exercise duration, workload, and abnormal results on ESE (P < .01 for all). On receiver operating characteristic curve analysis, CFVR < 2.3 was the best cutoff to predict abnormal results on ESE (area under the curve = 0.88 ± 0.06, P < .01). CONCLUSIONS: In patients with asymptomatic severe AS, noninvasive CFVR is correlated with exercise duration and workload, and low CFVR predicts abnormal results on ESE with good accuracy.

Drug-induced aortic valve stenosis: An under recognized entity.

BACKGROUND: We have been intrigued by the observation that aortic stenosis (AS) may be associated with characteristic features of mitral drug-induced valvular heart disease (DI-VHD) in patients exposed to valvulopathic drugs, thus suggesting that beyond restrictive heart valve regurgitation, valvulopathic drugs may be involved in the pathogenesis of AS. METHODS: Herein are reported echocardiographic features, and pathological findings encountered in a series of patients suffering from both AS (mean gradient >15mmHg) and mitral DI-VHD after valvulopathic drugs exposure. History of rheumatic fever, chest radiation therapy, systemic disease or bicuspid aortic valve disease were exclusion criteria. RESULTS: Twenty-five (19 females, mean age 62years) patients having both AS and typical features of mitral DI-VHD were identified. Mean transaortic pressure gradient was 32+/-13mmHg. Aortic regurgitation was ≥ mild in 24 (96%) but trivial in one. Known history of aortic valve regurgitation following drug initiation prior the development of AS was previously diagnosed in 17 patients (68%). Six patients underwent aortic valve replacement and 3 both aortic and mitral valve replacement. In the 9 patients with pathology analysis, aortic valvular endocardium was markedly thickened by dense non-inflammatory fibrosis, a characteristic feature of DI-VHD. CONCLUSION: The association between AS and typical mitral DI-VHD after valvulopathic drug exposure may not be fortuitous. Aortic regurgitation was usually associated to AS and preceded AS in most cases but may be lacking. Pathology demonstrated the potential role of valvulopathic drugs in the development of AS.

An expansible aortic ring to preserve aortic root dynamics after aortic valve repair.

OBJECTIVES: Aortic annuloplasty and preservation of root dynamics have been described as factors for durability of aortic valve repair. The objective of this study is to document the first clinical analysis of root dynamics after a standardized valve-sparing procedure for root aneurysms associating a calibrated expansible external aortic ring annuloplasty with a physiological remodelling of the aortic root (CAVIAAR technique: Conservative Aortic Valve surgery for aortic Insufficiency and Aneurysm of the Aortic Root). METHODS: Of the 600 patients operated on with the CAVIAAR technique, 60 consecutive patients from a single team underwent double independent reading of the echocardiographic analysis performed in the operative period and yearly after discharge until a maximum of 5-year follow-up. Forty-four patients had preoperative aortic insufficiency (AI) ≥grade 2 (73.3%) and 29 patients (48%) had bicuspid valves. RESULTS: The expansible aortic ring (median size 27 (25-27) mm) significantly reduced the aortic annular base diameter (from 28 (25-29) mm to 23 (21-24) mm) (P < 0.001) without a significant median transvalvular gradient increase (P = 0.545). Cusp repair was performed in 55 patients (91.7%). Operative mortality was 1.7% (1). During the median 19-month (95% confidential interval [11-26]) follow-up, annular diameter and cusp effective height remained stable. There were no valve-related reoperations. One patient died at 6 months postoperatively from congestive heart failure. Freedom from AI ≥grade 2 was 100% at 1-year follow-up and 96.8% ± 3.2% at 3-year follow-up. Systolic root expansibility of the four echocardiographic diameters (aortic annular base, sinuses of Valsalva level, sino tubular junction and tubular aorta) was maintained, throughout the follow-up period with the aortic annular base expansibility coefficient having consistently higher values than the three other levels. CONCLUSIONS: The expansible aortic ring achieved a complete calibrated external annuloplasty and maintained dynamics of the aortic root at mid-term follow-up. Whether this could be a factor for durability of aortic valve repair is currently under evaluation through the CAVIAAR study 10-year follow-up.

Aortic valve replacement with the perceval S bioprosthesis: single-center experience in 143 patients.

BACKGROUND AND AIM OF THE STUDY: Aortic stenosis (AS) is the most frequent heart valve disease in western countries, and its prevalence increases with age. Sutureless valves have recently become available that allow the surgical procedures to be shortened. The study aim was to assess clinical outcome after sutureless aortic valve replacement (SAVR) performed with the Perceval S bioprosthesis at the authors' institution. METHODS: Between June 2007 and November 2011, a total of 143 patients (78 females, 65 males; mean age 79.4 +/- 5.9 years) was prospectively enrolled and followed at the authors' center. The median preoperative logistic EuroSCORE was 12.04 +/- 10.7. Preoperatively, 58.8% of patients were in NYHA class III or IV, and the mean gradient and effective orifice area (EOA) were 38.8 +/- 17 mmHg and 0.76 +/- 0.24 cm2, respectively. Isolated SAVR was performed in 95 patients (66.4%), while associated procedures were necessary in 48 patients (33.6%). The follow up was 100% complete (mean 13.4 +/- 11.6 months; range: 0-5 years; total cumulative follow up 155 patient-years). RESULTS: The procedural success rate was 99.3%. The mean cross-clamp and cardiopulmonary bypass times were 32.0 +/- 14.9 min and 44.7 +/- 18.6 min, respectively. In-hospital mortality was 4.9% (n=7). Pacemaker implantation was required in seven patients (4.9%). Survival at five years was 85.5%. Reoperation was necessary in seven patients (4.9%); early reoperations were due to paravalvular leak (n = 3; 2.0%) and intra-prosthetic regurgitation (n=3; 2.0%). One late reoperation (at 29 months) was required, due to fibrous pannus overgrowth. One late endocarditis (0.7%) occurred at 26 months and was medically treated. No structural valve deterioration occurred during the follow up. At 12 months, 94.4% of survivors were in NYHA class I-II, and the mean pressure gradient and EOA were 9.0 +/- 3.4 mmHg and 1.60 +/- 0.3 cm2, respectively. CONCLUSION: The Perceval S valve appears to be a safe option for SAVR, though further follow up is needed to evaluate the long-term outcome with this bioprosthesis.

Decreased right ventricular lateral wall velocities early after cardiac surgery.

BACKGROUND: Right ventricular (RV) function is less often monitored than left ventricular (LV) function and might influence the postoperative period in patients undergoing coronary bypass or heart valve surgery. Our objective was to compare RV lateral wall velocities before and soon after heart surgery. METHODS: We examined 87 patients before and at a median time of 5 days after surgery with tissue Doppler echocardiography. On-pump coronary artery bypass grafting was performed in 40 patients, and valvular surgery in 47 patients. The pulsed Doppler sample was positioned at the midportion of the RV lateral wall, on the septum and on the LV lateral wall to record peak systolic (S), early (E) and late (A) diastolic tissue Doppler velocities. RESULTS: We observed lower values of LV end diastolic volume and left atrial area (P < 0.001) but no differences in RV fractional area change as well as LV ejection fraction between before and after surgery. RV S, E, and A were dramatically lower in the postoperative group (P < 0.001 between before and after surgery), as well as septal S, E, and A (P < 0.005 between before and after). No change occurred on LV lateral S and A, whereas LV lateral wall E velocity was slightly higher in the postoperative group (P < 0.05). CONCLUSIONS: Tissue Doppler velocities of the RV free wall are reduced significantly after cardiac surgery despite no reduction in RV fractional area change.

Beating heart revascularization with minimal extracorporeal circulation in patients with a poor ejection fraction.

BACKGROUND: Coronary artery bypass grafting with cardioplegia in patients with a low ejection fraction carries a risk of myocardial ischemia. Beating heart surgery is associated with hemodynamic changes when the heart is manipulated. We assessed an alternative: minimal extracorporeal circulation for coronary artery bypass grafting on a beating heart in patients with a poor ejection fraction. METHODS: From January 2000 to January 2002, 50 patients with an ejection fraction of less than 35%, who represented 10% of all patients undergoing coronary artery procedures, underwent revascularization on a beating heart with assistance. We used a closed cardiopulmonary bypass system with a centrifugal pump without reservoir, and the surgical strategy was modified to avoid aortic cross-clamping and to decrease bypass time. RESULTS: The main preoperative characteristics were: age (mean +/- SD) of 64 +/- 11.2 years (range, 41-87 years), 35 male patients (70%), mean left ejection fraction of 24.8% +/- 11.2%, and a mean EuroSCORE of 5.8 +/- 2.7. Revascularizations of 146 distal anastomoses (2.9 +/- 0.7 grafts/patient) were completed. Twelve percent were double bypass, 86% were triple bypasses, and 2% were quadruple bypasses; the mean bypass time was 64.2 +/- 26.2 minutes. The mean graft number was 2.9, and the hospital mortality was 2%. Perioperative hematocrit levels were 30.1%, and 26% of patients received transfusions. Postoperative data showed a median extubation time of 9 hours, a median intensive care unit stay of 48 hours, and a hospital stay of 8 +/- 2 days. Postoperative complications included inotropic support (14%), cerebrovascular events (2%), reoperation for homeostasis (4%), delayed sternal closure (2%), and mediastinitis (2%). Peak troponin Ic level remained a low 2.4 +/- 1.9 g/mL. Follow-up at 6 months was complete with 1 late mortality and with a mean ejection fraction of 30.5% +/- 10.8% for the survivors. CONCLUSIONS: Coronary revascularization on a beating heart with extracorporeal assistance can be done in patients with a low ejection fraction. It avoids the myocardial injury associated with aortic cross-clamping and allows safe and complete coronary revascularization.