Christophe Tribouilloy

Monitoring of respiratory variations of aortic blood flow velocity using esophageal Doppler

ObjectiveThe purpose of this study was to determine whether monitoring of respiratory changes in aortic blood flow velocity, recorded by esophageal Doppler, could be used to detect changes in volume depletion.DesignAnimal study.Animals and interventionsAfter general anesthesia and tracheotomy, ten New Zealand female rabbits, weighing 4–4.5xa0kg were studied under mechanical ventilation at a fixed tidal volume; during this time 5-ml blood samples were withdrawn (in increments up to a total of 30xa0ml) and then retransfused.Measurements and resultsAt each step, systolic (SBP), diastolic (DBP), pulse (PP) pressures and maximum descending aortic blood flow (V) were recorded. Respiratory changes of V (ΔV), SBP (ΔSBP) and PP (ΔPP) were calculated as the difference of maximal and minimal values divided by their respective means and expressed as a percentage. The amount of blood withdrawn correlated negatively with SBP, DBP, PP and V and positively with ΔSBP, ΔPP and ΔV. Among these parameters, ΔV correlated best with the amount of blood withdrawn (r=0.89, p<0.001) and it was the most accurate index of volume depletion.ConclusionMonitoring of the respiratory variation in V, calculated by esophageal Doppler technique, seems to be a highly accurate index of blood volume depletion and restitution.

Comparison of clinical and morphological characteristics of Staphylococcus aureus endocarditis with endocarditis caused by other pathogens

Objectives: To analyse clinical, echocardiographic, and prognostic characteristics of Staphylococcus aureus infective endocarditis (IE) compared with endocarditis caused by other pathogens. Design: Cohort study. Methods: 194 consecutive patients with definite IE according to the Duke criteria prospectively examined by transthoracic and transoesophageal echocardiography were enrolled. Patients without identified microorganisms were excluded. The S aureus IE group (n u200a=u200a 61) was compared with the group with IE caused by other pathogens (n u200a=u200a 133). Results: Compared with IE caused by other pathogens, S aureus IE was characterised by severe co-morbidity, a shorter duration of symptoms before diagnosis, and a higher prevalence of right sided IE, cutaneous portal of entry, and history of renal failure. Severe sepsis, major neurological events, and multiple organ failure were more frequent during the acute phase in S aureus IE. In-hospital mortality (34% v 10%, p < 0.001) was higher in patients with S aureus IE and the 36 month actuarial survival rate was lower in S aureus IE than in IE caused by other pathogens (47% v 68%, p u200a=u200a 0.002). Multivariate analyses identified S aureus infection as a predictive factor for in-hospital mortality and for overall mortality. Conclusions:S aureus IE compared with IE caused by other pathogens occurs in a more debilitated clinical setting and is characterised by a higher prevalence of severe sepsis, major neurological events, and multiple organ failure leading to higher mortality.

Left Atrial Size is a Potent Predictor of Mortality in Mitral Regurgitation Due to Flail Leaflets: Results from a Large International Multicenter Study

Background— Left atrium (LA) enlargement is common in organic mitral regurgitation (MR) and is an emerging prognostic indicator. However, outcome implications of LA enlargement have not been analyzed in the context of routine clinical practice and in a multicenter study. Methods and Results— The Mitral Regurgitation International DAtabase (MIDA) registry enrolls patients with organic MR due to flail leaflets, diagnosed in routine clinical practice, in 5 US and European centers. We investigated the relation between LA diameter and mortality under medical treatment and after mitral surgery in 788 patients in sinus rhythm (64±12 years; median LA, 48 [43 to 52] mm). LA diameter was independently associated with survival after diagnosis (hazard ratio, 1.08 [1.04 to 1.12] per 1 mm increment). Compared with patients with LA <55 mm, those with LA ≥55 mm had lower 8-year overall survival (P<0.001). LA ≥55 mm independently predicted overall mortality (hazard ratio, 3.67 [1.95 to 6.88]) and cardiac mortality (hazard ratio, 3.74 [1.72 to 8.13]) under medical treatment. The association of LA ≥55 mm and mortality was consistent in subgroups. Similar excess mortality associated with LA ≥55 mm was observed in asymptomatic and symptomatic patients (P for interaction, 0.77). In patients who underwent mitral surgery, LA ≥55 mm had no impact on postoperative outcome (P>0.20). Mitral surgery was associated with greater survival benefit in patients with LA ≥55 mm compared with LA <55 mm (P for interaction, 0.008). Conclusions— In MR caused by flail leaflets, LA diameter ≥55 mm is associated with increased mortality under medical treatment, independent of the presence of symptoms or left ventricular dysfunction.

Quantitation of mitral regurgitation: rationale, approach, and interpretation in clinical practice

Quantitation of mitral regurgitation has made considerable progress is recent years, providing unique insights into the physiology of the condition, and providing essential tools for a proactive modern management of patients with MRnnMitral regurgitation (MR) is a valvar haemodynamic alteration which is the focus of intense interest despite the decline of rheumatic disease, because of its high frequency.1 Indeed, in our current aging population, MR is most often caused by diseases prevalent in the elderly, either degenerative lesions (such as mitral valve prolapse or ruptured chordae) or functional alterations (the consequence of ventricular dysfunction).2 Hence, the assessment of MR is a key task of internists, cardiologists, and cardiac surgeons and has been transformed by Doppler echocardiography. In the past decade new methods and new concepts have been developed for the quantitation of MR, which have been detailed by Irvine and colleagues in this supplement to Heart .3 As one may ponder the incremental benefit of new approaches, it is important to review their rationale, to delineate how to integrate them in a global approach, and how to interpret these new results.nn### Rationale 1: MR impacts seriously on outcomennSevere MR has the reputation of being well tolerated for many years. Although this is occasionally true, this dogma has little support from outcome data. Indeed, when we examined the long term outcome of patients with flail leaflets that epitomise severe MR,4 excess mortality,5 and high morbidity6,7 were observed, with high rates of heart failure, atrial fibrillation,7 and even sudden death.6 It is also remarkable that in functional MR, although the disease is not initially valvar in nature, the higher the degree of MR, the worse the …

Mutations in DCHS1 cause mitral valve prolapse.

Mitral valve prolapse (MVP) is a common cardiac valve disease that affects nearly 1 in 40 individuals. It can manifest as mitral regurgitation and is the leading indication for mitral valve surgery. Despite a clear heritable component, the genetic aetiology leading to non-syndromic MVP has remained elusive. Four affected individuals from a large multigenerational family segregating non-syndromic MVP underwent capture sequencing of the linked interval on chromosome 11. We report a missense mutation in the DCHS1 gene, the human homologue of the Drosophila cell polarity gene dachsous (ds), that segregates with MVP in the family. Morpholino knockdown of the zebrafish homologue dachsous1b resulted in a cardiac atrioventricular canal defect that could be rescued by wild-type human DCHS1, but not by DCHS1 messenger RNA with the familial mutation. Further genetic studies identified two additional families in which a second deleterious DCHS1 mutation segregates with MVP. Both DCHS1 mutations reduce protein stability as demonstrated in zebrafish, cultured cells and, notably, in mitral valve interstitial cells (MVICs) obtained during mitral valve repair surgery of a proband. Dchs1+/− mice had prolapse of thickened mitral leaflets, which could be traced back to developmental errors in valve morphogenesis. DCHS1 deficiency in MVP patient MVICs, as well as in Dchs1+/− mouse MVICs, result in altered migration and cellular patterning, supporting these processes as aetiological underpinnings for the disease. Understanding the role of DCHS1 in mitral valve development and MVP pathogenesis holds potential for therapeutic insights for this very common disease.

Bivalvular mechanical Mitral-Aortic valve replacement in 254 patients: Long-Term results—a 22-year follow-up

BACKGROUNDnWe have retrospectively studied 254 patients who underwent a bivalvular mechanical mitral-aortic replacement in the cardiovascular and thoracic surgery unit of Nantes from 1979 to 1989. The follow-up was 22 years (1979 to 2001). The last patient was operated on 12 years before the end of the follow-up.nnnMETHODSnAll mitral prostheses were St. Jude Medical (SJM) bileaflet valves, and the aortic prostheses were 124 monodisc Björk-Shiley valves, 3 Sorin prostheses, and 127 St. Jude Medical bileaflet prostheses. The mean age was 56.8 +/- 8.5 years with a sex ratio equal to 1. Rheumatism as the etiology predominated with 79.5%. Ninety-seven percent of the patients were followed for a total of 2,779 patient-years and a mean of 11.7 years.nnnRESULTSnOperative mortality was 7.08%. Freedom from overall mortality and valve-related mortality at 22 years were 45.7% +/- 3.6% and 73.1% +/- 3%, respectively. The linearized rates of thromboembolic and hemorrhagic events were 1.07% and 0.9% per patient-year, respectively. Multivariate analysis showed age (p < 0.002), sex (p < 0.01), and degenerative etiology (p = 0.04) as independent factors of late mortality, and age, sex, degenerative disease, and tricuspid pathology were related to valve-related mortality.nnnCONCLUSIONSnThis study shows good results after mechanical mitral-aortic replacement in terms of survival rate and quality of life in surviving patients, and outlines the factors influencing long-term results as compared with isolated mitral valve replacement.

The MIDA Mortality Risk Score: development and external validation of a prognostic model for early and late death in degenerative mitral regurgitation

AimsnIn degenerative mitral regurgitation (DMR), lack of mortality scores predicting death favours misperception of individual patients risk and inappropriate decision-making.nnnMethods and resultsnThe Mitral Regurgitation International Database (MIDA) registries include 3666 patients (age 66u2009±u200914u2009years; 70% males; follow-up 7.8u2009±u20095.0u2009years) with pure, isolated, DMR consecutively diagnosed by echocardiography at tertiary (European/North/South-American) centres. The MIDA Score was derived from the MIDA-Flail-Registry (2472 patients with DMR and flail leaflet-Derivation Cohort) by weighting all guideline-provided prognostic markers, and externally validated in the MIDA-BNP-Registry (1194 patients with DMR and flail leaflet/prolapse-Validation Cohort). The MIDA Score ranged from 0 to 12 depending on accumulating risk factors. In predicting total mortality post-diagnosis, the MIDA Score showed excellent concordance both in Derivation Cohort (cu2009=u20090.78) and Validation Cohort (cu2009=u20090.81). In the whole MIDA population (nu2009=u20093666 patients), 1-year mortality with Scores 0, 7-8, and 11-12 was 0.4, 17, and 48% under medical management and 1, 7, and 14% after surgery, respectively (Pu2009<u20090.001). Five-year survival with Scores 0, 7-8, and 11-12 was 98u2009±u20091, 57u2009±u20094, and 21u2009±u200910% under medical management and 99u2009±u20091, 82u2009±u20092, and 57u2009±u20099% after surgery (Pu2009<u20090.001). In models including all guideline-provided prognostic markers and the EuroScoreII, the MIDA Score provided incremental prognostic information (Pu2009≤u20090.002).nnnConclusionnThe MIDA Score may represent an innovative tool for DMR management, being able to position a given patient within a continuous spectrum of short- and long-term mortality risk, either under medical or surgical management. This innovative prognostic indicator may provide a specific framework for future clinical trials aiming to compare new technologies for DMR treatment in homogeneous risk categories of patients.