Regurgitant flow of mitral valve prostheses: an intraoperative transesophageal echocardiographic study

Mitral valve paravalvular leaks: Comprehensive review of literature

BACKGROUND

Mitral paravalvular leaks (mPVL) are a recognized complication for patients with mitral valve prostheses. Although clinically insignificant for many patients, it may pose life-threatening haemolysis and regurgitation-induced heart failure, and so clinicians should have a high index of suspicion in the presence of new symptoms.

AIMS

This review discusses the pathogenesis, clinical features, diagnosis, imaging and treatment of mPVLs.

METHODS

A comprehensive literature search was performed using PubMed, EMBASE, Cochrane database, Google Scholar and Ovid. Search terms used included "mitral valve paravalvular leak," "transthoracic echocardiography," "2D transoesophageal echocardiography," "3D transoesophageal echocardiography," "cardiac computed tomography," (CT) "cardiac magnetic resonance imaging," "intracardiac echocardiography," "cinefluoroscopy," "fluoroscopy," and "percutaneous closure."

RESULTS

All patients with mPVLs should undergo regular full evaluation, including patient history, physical examination, laboratory work-up, imaging, and referral, if necessary. Echocardiography is fundamental to the diagnosis, and is augmented with cardiac magnetic resonance imaging, cardiac computerized tomography and fluoroscopy for further characterization and procedural planning amongst the structural heart team.

CONCLUSION

The prevalence of mPVL is expected to increase proportionally to the growing number of surgical and transcatheter valve replacements conducted in the ageing population. Multimodal imaging is instrumental in guiding diagnostic and therapeutic strategies when managing mPVLs. Advances in imaging and capabilities of transcather devices will prompt growing uptake of percutaneous treatment over conventional, higher-risk surgery for mPVL management.

Systematic transoesophageal echocardiography after mitral valve replacement: Rates and determinants of paravalvular regurgitation

BACKGROUND

With the emergence of transcatheter mitral valve replacement, it appears crucial to provide contemporary references with which this new technology can be compared. At our institution, transoesophageal echocardiography is systematically performed before discharge after surgical mitral valve replacement.

AIM

To evaluate the rate and determinants of paravalvular regurgitation after surgical mitral valve replacement.

METHODS

We collected medical history, indication, type of surgery and in-hospital outcome in all consecutive patients who underwent a mitral valve replacement in the past 2 years at our institution. Paravalvular regurgitation was assessed semiquantitatively using transoesophageal echocardiography before discharge.

RESULTS

We enrolled 399 patients (mean age 61±16 years; 58% women; 27% with a history of cardiac surgery). Mitral valve replacement was performed mainly for rheumatic disease (44%). Most patients were severely symptomatic (70% in New York Heart Association class III/IV). A mechanical prosthesis was implanted in 60% and a bioprosthesis in 40%. In-hospital mortality was 10%. Transoesophageal echocardiography was performed in 310 patients (77%); the main reasons for not performing transoesophageal echocardiography were frailty (n=40, 10%), early death (n=19, 5%) and contraindication for transoesophageal echocardiography (n=10, 3%). The overall rate of paravalvular regurgitation was 8% (n=25); a grade ≥2 was observed in five patients (2%), and two patients had to be reoperated on. Mitral annular calcification was the main factor associated with paravalvular regurgitation (P=0.01).

CONCLUSIONS

Surgical mitral valve replacement was associated with significant in-hospital mortality and morbidity. Using systematic transoesophageal echocardiography assessment, paravalvular regurgitation was not uncommon (8%), and was significantly linked to mitral annulus calcification. However, clinically significant leakage (≥grade 2) was rare (2%).

Percutaneous Device Closure of Paravalvular Leak: Combined Experience From the United Kingdom and Ireland

BACKGROUND

Paravalvular leak (PVL) occurs in 5% to 17% of patients following surgical valve replacement. Percutaneous device closure represents an alternative to repeat surgery.

METHODS

All UK and Ireland centers undertaking percutaneous PVL closure submitted data to the UK PVL Registry. Data were analyzed for association with death and major adverse cardiovascular events (MACE) at follow-up.

RESULTS

Three hundred eight PVL closure procedures were attempted in 259 patients in 20 centers (2004-2015). Patient age was 67±13 years; 28% were female. The main indications for closure were heart failure (80%) and hemolysis (16%). Devices were successfully implanted in 91% of patients, via radial (7%), femoral arterial (52%), femoral venous (33%), and apical (7%) approaches. Nineteen percent of patients required repeat procedures. The target valve was mitral (44%), aortic (48%), both (2%), pulmonic (0.4%), or transcatheter aortic valve replacement (5%). Preprocedural leak was severe (61%), moderate (34%), or mild (5.7%) and was multiple in 37%. PVL improved postprocedure (P<0.001) and was none (33.3%), mild (41.4%), moderate (18.6%), or severe (6.7%) at last follow-up. Mean New York Heart Association class improved from 2.7±0.8 preprocedure to 1.6±0.8 (P<0.001) after a median follow-up of 110 (7-452) days. Hospital mortality was 2.9% (elective), 6.8% (in-hospital urgent), and 50% (emergency) (P<0.001). MACE during follow-up included death (16%), valve surgery (6%), late device embolization (0.4%), and new hemolysis requiring transfusion (1.6%). Mitral PVL was associated with higher MACE (hazard ratio [HR], 1.83; P=0.011). Factors independently associated with death were the degree of persisting leak (HR, 2.87; P=0.037), New York Heart Association class (HR, 2.00; P=0.015) at follow-up and baseline creatinine (HR, 8.19; P=0.001). The only factor independently associated with MACE was the degree of persisting leak at follow-up (HR, 3.01; P=0.002).

CONCLUSION

Percutaneous closure of PVL is an effective procedure that improves PVL severity and symptoms. Severity of persisting leak at follow-up is independently associated with both MACE and death. Percutaneous closure should be considered as an alternative to repeat surgery.

The Impact of Intraoperative Echocardiography on Clinical Outcomes Following Adult Cardiac Surgery

Over the past 30 years, intraoperative echocardiography has become an invaluable diagnostic tool and monitor of cardiac performance for the management of cardiac surgical patients. The essential information provided by intraoperative echocardiography regarding hemodynamic management, cardiac valve function, congenital heart lesions, and great vessel pathology has contributed to its widespread popularity. Numerous investigations have been conducted in an attempt to specifically demonstrate a beneficial impact of intraoperative echocardiography in cardiac surgery. However, there is a relative paucity of data derived from prospective trials in which the use of intraoperative echocardiography has been randomized among various cardiac surgical patient populations to formally ascertain, rather than simply infer, its putative impact on perioperative decision-making and clinical outcomes. Ironically, the popularity of intraoperative echocardiography has imposed ethical limitations on performing randomized trials in patient populations for whom significant benefit has been previously inferred. Nonetheless, significant evidence has been published to support its almost universal acceptance as an important perioperative diagnostic tool and monitor for cardiac surgical patients. This review focuses on the impact of intraoperative echocardiography on clinical outcomes in the more common adult cardiac surgical scenarios, including coronary artery bypass graft surgery, mitral and aortic valve surgery, and in evaluating the intrathoracic aorta.

Noninvasive imaging of the heart and coronary arteries

There are multiple imaging modalities currently available to noninvasively evaluate the heart and coronary arteries. Choosing the most appropriate modality depends on the pertinent clinical question and the underlying patient characteristics. This article provides an overview of the fields of echocardiography, myocardial perfusion imaging, cardiac computed tomography, and cardiac magnetic resonance imaging, with particular attention to specific clinical applications for cardiac surgery patients.

Prevalence and clinical significance of incidental paraprosthetic valvar regurgitation: a prospective study using transoesophageal echocardiography

OBJECTIVE

To assess the prevalence, mechanisms, and significance of paraprosthetic regurgitation detected incidentally by transoesophageal echocardiography (TOE) in patients after heart valve replacement.

DESIGN

Prospective observational study.

SETTING

Tertiary referral centre.

PATIENTS

360 consecutive patients (mean (SD) age 65.8(9.5) years, 193 women) undergoing elective first ever valve replacement.

METHODS

Postoperative and follow up TOE, and tests for haemolysis and anaemia.

RESULTS

There were 243 aortic, 90 mitral, and 27 double valve replacements, using 316 mechanical and 44 tissue valves, giving 270 aortic and 117 mitral valves. One patient with severe paraprosthetic mitral regurgitation underwent immediate reoperation and was excluded from subsequent analyses. Paraprosthetic jets were detected around 16 (6%) of the aortic and 38 (32%) of the mitral valves (p < 0.05) at the postoperative study. Follow up TOE was available for 151 aortic and 67 mitral valves, 0.9 (0.5) years after operation. Paraprosthetic jets were present in 15 (10%) of the aortic and 10 (15%) of the mitral valves (NS). Two thirds of the aortic and a fifth of the mitral jets were new. Paraprosthetic jets were more common in aortic valves in a supra-annular (12 of 88, 14%) than in an intra-annular position (4 or 182, 2%; p < 0.005) and in mitral valves inserted with continuous (36 of 88, 41%) rather than interrupted sutures (2 of 28, 7%; p < 0.001). Lactate dehydrogenase concentration was higher in patients with paraprosthetic jets than in those without (752 (236) v 654 (208) IU/l, p < 0.001). Haemoglobin and haptoglobin concentrations were not different.

CONCLUSIONS

Small paraprosthetic leaks are common, are related to surgical factors, are not associated with increased subclinical haemolysis, and are benign during the first year after heart valve replacement.

What does transesophageal echocardiography add to valvular heart surgery?

No single monitoring tool in the last decade has had more of an effect on intraoperative decision making and surgical management of cardiac valvular pathologies than has TEE. It has become the standard of care for evaluating reparative valvular procedures, thus providing an immediate gauge of the surgical results and helping to avoid suboptimal surgical outcomes. As the technology of TEE and its application advance, so too should the ability to diagnose and manage valvular pathologies, broaden the range of surgical options, and ultimately improve patient outcomes.

[Usefulness of intraoperative echocardiography for the management of mitral regurgitation]

Intraoperative transesophageal echocardiography is crucial in the management of patients with mitral regurgitation. In fact, a vast majority mitral insufficiencies may actually be repaired. This kind of surgery require an excellent definition of anatomic lesions and mechanisms of mitral regurgitation in order to optimize the result of the repair. In this field, intraoperative echocardiographic findings are complementary with anatomical findings for the surgeon. Before surgery, intraoperative echography help to describe all valvular lesions and mechanisms of the regurgitation. Three-dimensional echocardiography may be obtained using intraoperative echography and may be useful in mitral valve prolapse to better define the location and size of prolapse and to communicate informations to the surgeon. After repair, echographyallow the control of the result and also of right and left ventricular function. In case of major abnormality such as residual significant mitral regurgitation or important intra-ventricular obstruction, a second procedure may be required. The collaboration between the echographist and the surgeon is crucial to obtain the best results in mitral valve repair. Indications for intraoperative echocardiography are dependent on the experience of the surgeon and the complexity of mitral lesions to repair.

Evaluation of mitral valve disease using transesophageal echocardiography

In the past 10 years, clinical application of transesophageal echocardiography (TE) has grown explosively. Intraoperative TE offers a powerful diagnostic and monitoring tool for the physicians in the cardiac operating room. The use of TE revolutionizes the assessment of patients with mitral valve disease. Surgical decisions are often altered based on the information obtained from TE. This review describes the basic features of TE as well as its uses in the intraoperative setting for evaluation of the mitral valve.

The role of intraoperative echocardiography in valve surgery

The widespread use and popularity of intraoperative echocardiography (IOE) has resulted from advances in cardiac surgery, reparative procedures for valvular heart disease and, most specifically, mitral valve repair. IOE has grown exponentially and is becoming an integral part of the planning and evaluation of many types of surgical procedures such that it is now considered standard of care especially for the perioperative management of patients undergoing mitral and aortic valve repair. This article discusses the application of intraoperative echocardiography and focus specifically on valvular heart disease as this represents the most widely accepted indication for the procedure in current clinical practice.

Assessment of Renal Perfusion in a Canine Model Using FS069, A New Transpulmonary Echocontrast Agent

We have previously demonstrated the safety and efficacy of FS069, a new transpulmonary echocontrast agent, for myocardial opacification. To our knowledge, no information exists regarding the use of this agent for transcutaneous assessment of renal perfusion. We studied 14 mongrel dogs using intravenously administered FS069. Renal ultrasound imaging was performed with a Hewlett-Packard Sonos 1500 using a 3.5-MHz transducer. Renal blood flow (ReBF) was altered using renal artery occlusion in four dogs and dipyridamole (0.56 mg/kg IV) in ten dogs. Renal perfusion was quantitatively assessed before and after each intervention using background subtracted peak intensity. ReBF was assessed with radiolabeled microspheres in ten dogs. Renal opacification was observed in all 14 dogs at baseline. The intravenous contrast dose required to produce optimal renal opacification ranged from 0.3-0.7 cc. After renal artery occlusion, peak intensity was reduced from 5.4 +/- 5.8 to 0.93 +/- 1.1 units (r = 0.99, P < 0.008). As expected, blood pressure and ReBF dropped in all ten dogs after dipyridamole administration. Interestingly, peak intensity increased in all but one dog. An inverse correlation (r = -0.75, P = 0.02) was observed between ReBF and peak intensity (percent change from baseline). The inverse relation between ReBF and peak intensity observed suggests vasoconstriction of the afferent arterioles in response to dipyridamole and a reduced clearance of the contrast. These findings are in agreement with previous data demonstrating decreased renal thallium clearance postdipyridamole administration. Our data document the feasibility to assess renal perfusion under various flow states after intravenous injection of FS069.

Echocardiography and Doppler assessment of prosthetic heart valves with transesophageal echocardiography

This article examines the use of transesophageal echocardiography (TEE) in the assessment of prosthetic heart valves. A summary of the commonly used artificial valves and their physiologic regurgitant flow patterns, as identified by color Doppler imaging, is presented. The hemodynamic evaluation of prosthetic valve stenosis using Doppler techniques is reviewed, and the diagnostic utility of TEE in identifying the complications of cardiac prostheses is discussed.