STENTED TISSUE HEART VALVE PROSTHESES “BIOLAB KA-PT” FOR AORTIC VALVE REPLACEMENT IN PATIENTS OVER 60 YEARS OF AGE
Drs. S.I. Zheleznev, M.V. Isayan, D.A. Astapov, Novosibirsk Federal Research Institute of Circulation Pathology – Novosibirsk, Russia
Purpose of the study
We assessed immediate results of “BioLab KA-PT” stented xenopericardial valves use for aortic valve replacement (AVR).
Material and methods
Since January 2009 till May 2010 165 patients received “BioLab KA-PT” as aortic valve substitute. Mean age was 69.3±4.5 years (60–82), there were 74 (44,8%) men. Average NYHA functional class was III (II, III). Sizes of the prostheses used were the following: “20” in 53 patients (32%), “22” in 76 (46%), “24”in 34 (20%), and “26”- in 2 (1.2%). Average aortic crossclamp time for isolated AVR was 69.3±14.1 min.
Results
There were 3 (1.8%) hospital deaths и 2 (1,2%) cases of early prosthetic valve dysfunction. In 1 case in was valve thrombosis at 25 day after surgery, and 1 case of the early (26 day) prosthetic regurgitation; for both of them we successfully performed redo surgery. In 1 case we found Type II aortic dissection at 30th day after valve surgery, for which supracoronary replacement of ascending aorta was performed. Prosthetic infective endocarditis rate was 4.8% (8 patients). At the postoperative echocardiography on discharge we found LV EDV index reduction from 62.3±26 до 53.8±17 ml/m2 (р=0.005), LV mass index reduction from 383.5±99.7 to 181.8±47.1 g/m2 (р=0.003), respectively. There were no significant changes in LV ejection fraction (62±11 and 61±9%, respectively, р=0.4). and new hypocinetic or akinetic LV areas. Peak AV prosthesis gradient (PAVPG) was. 19.9±6.4 (7- 40) mm Hg for the entire group. PAVPG analysis in different valve sizes revealed moderate correlation (р < 0.05). Average PAVPG in size “20” was 22.8±5.953, in size “22” – 19.1±5.3, in size“24” – 17.4±7.8, and in size “26” – 13.8±1.6 mm Hg. In all the cases there were complete systolic opening of the prosthetic leaflets, and satisfactory closure in diastole. Average effective area of the valve orifice were 2.6±0.2 cm2: for the size “20” – 2.4±0.2, size “22” – 2.6±0.2 ; size 24 – 2.8±0.1, size 26 – 2.9±0.1 cm2.
Conclusions
Stented bioprosthesis “BioLab KA-PT” is shown good clinical and hemodynamic results in early terms after AVR. Nevertheless, long-term follow up studies are needed, comparing “BioLab KA-PT” to other models of tissue valves.
CARDIO VASCULAR MAGNETIC RESONANCE IN CONGENITAL HEART DISEASE
Dr. Olivier Wittenberg, Marseille, France
Introduction
Cardiovascular magnetic resonance imaging (CMR) plays an essential role in the evaluation and follow up of congenital heart disease (CHD) particularly in adults (Grown up congenital heart disease -GUCH-) which subgroup is nowadays predominant among the entire population of CHD patients.
CMR
1- provides safe high resolution reproducible imaging of both simple and complex anatomies encountered, unlimited by acoustic windows and capable of tissue characterization.
2- Is devoid of ionizing radiation and provides superior 3 D spatial resolution to echocardiography and superior temporal resolution to CT making it gold standard for various cardiac and great vessels imaging. This imaging modality is particularly efficient and useful for evaluation of accurate cardiac function, volumetric measurement, viability perfusion and finally detection of cardiac fibrosis
3- Has become an essential facility in the specialized unit playing an important role in the choice and timing of (re)intervention
CMR limitations
1- Patient compliance (shortness of breath, claustrophobia)
2- Stable ECG is mandatory (ECG gated cine images), arrhythmia leads to a lot of artifacts and provides poor spatial resolution
3- Implanted PMK and defibrillator definitively preclude CMR
4- Appropriate skill and experience from the radiologist/cardiologist who perform the examination
Methods
The comprehensive imaging approach comprises of 3 modules
Cine imaging of the entire heart
By obtaining a stack of cine short axis views from ventricular apex to the atria posteriorely , a stack of 4 chamber cine images and finally a stack of left and right outflow track images.
Valvular assessment
The qualitative assessment of all cardiac valves for regurgitation and stenoses is observed by echo planar cine images and balanced steady state free precession (BSSFP) sequences. Flow quantification is easily performed through the ascending aorta and main pulmonary artery with measure of the appropriate velocity encoding to obtain peak velocity and gradients comparable to measurements obtained with echocardiography.
Contrast enhanced MRI
A 3D magnetic resonance angiography enhanced by contrast agent of the great vessels (MRA) is routinely obtained and is crucial to detect vascular (aortic or pulmonary) abnormalities or systemic and venous connections; the analysis is accurate for structures up to 2mm diameter.
Clinical indications
There are several groups of indications for CMR when assessing CHD in clinical practice
• Adjunct to echocardiography
Suboptimal echo findings or ambiguous measurement
Gold standard method for ventricular volumes, mass, right and left EF measurement Quantification of valvular regurgitation and stenoses (aortic and pulmonary valves) to corroborate or amend the echo values prior to clinical decisions.
• Superiority of CMR
Evaluation of the entire Aorta
Accurate identification and measurement of Aortic root+ Arch in pathology such as hypoplasia, coarctation, aneurysm with assessment of associate pathology (bicuspid aortic valve, valvular regurgitation, LV hypertrophy).
Right Ventricle
RV out track obstruction, RV-Pulmonary artery conduits, Repaired ToF , Pulmonary atresia
Systemic and pulmonary veins evaluation
Complex anatomy (TGV – Switch-Mustard/Senning) , FONTAN Cavopulmonary connections
Tissue characterization (Fibrosis)
Conclusion
Trans thoracic echo remains the first line imaging modality in CHD especially for children
CMR provides a superior and accurate measurement of biventricular function and volumes accurate anatomy of the CHD and is very useful in the follow up of Adults after repairs of ToF,aortic coarctation,TGA and for those with (un)operated patients complex malformations
In the future CMR should be considered as a necessary facility in a center specialized in the care of congenital heart disease.
TAVI IN 2011 : WHAT NEWS ?
Pr. Alec Vahanian, Bichat Hospital, Paris, France
TAVI has been shown to be feasible (procedural success rates >90%) in patients with high surgical risk using transfemoral, transapical or less commonly, subclavian access, or direct transaortic access. In the absence of anatomical contraindications, a transfemoral approach is the preferred technique in most centres, although no direct comparisons are available between either transfemoral and transapical or other approaches. Similarly there is no direct comparison between the two available devices. Reported 30-day mortality ranges from 5 to15%. The main procedure- related complications include: stroke (~1-5%), need for new pacemaker (up to 7% for the balloon expanded, up to 40% for the self expanding system), and vascular complications (up to 20%). Paravalvular regurgitation is common, although reported to be trace or mild in the majority of patients and rarely clinically relevant. More than mild AR may impact long term survival. This remains a concern and requires careful further followup and critical evaluation. Approximately 1-2% of TAVI patients require immediate cardiac surgery for life-threatening complications.
TAVI provides haemodynamic results that are slightly superior to conventional stented bioprostheses, particularly in patients with a small aortic annulus. Reported 1-year survival for TAVI ranges from 60 to 80%, largely depending on the severity of comorbidities. Most survivors experience significant improvement in health status and quality of life. However, long-term durability of these valves remains to be addressed, although 3-5 year results are promising.
Patients considered unsuitable for AVR after surgical consultation clearly benefit from TAVI compared to conservative treatment including balloon valvuloplasty, as demonstrated by a randomized trial (1-year mortality 31 vs 51%, and significantly better symptomatic improvement). The first randomized trial comparing TAVI and surgical AVR in high risk but not inoperable patients showed TAVI to be non-inferior for all cause mortality at 1 year (24.2% vs 26.8%) with marked functional improvement in both groups. The analysis of secondary end points showed TAVI carried a higher risk of cerebrovascular events and vascular complications and a higher incidence of paravalvular leaks, although mostly trace and mild. Conversely, bleeding and post operative atrial fibrillation were more frequent after surgery.
TAVI should only be performed in hospitals with cardiac surgery on-site. A “heart team†consisting of cardiologists and cardiac surgeons that assesses individual patient risks, as well as the technical suitability of TAVI and access issues, should be best able to make decisions in this patient population.
Contraindications, both clinical and anatomic should be identified. Eligible patients should have a life expectancy of more than one year and should also be likely to gain improvement in their quality of life, taking into account their comorbidities.
Based on current data TAVI is recommended in patients with severe symptomatic AS who are considered unsuitable for conventional surgery because of severe comorbidities by the team. Among high risk patients who are still candidates for surgery, TAVI should be considered as an alternative to surgery in patients in whom the heart team considers that both options are available. In such cases the decision should be individualised taking into consideration the respective advantages of both techniques…
At the present stage TAVI should not be performed in patients at moderate to low risk for surgery and trials are required in this population.
PERCUTANEOUS TREATMENT OF MITRAL REGURGITATION
Pr. Alec Vahanian, Bichat Hospital, Paris, France
The only catheter based intervention which has been evaluated in organic Mitral Regurgitation (MR) is the edge to edge procedure. Data from the EVEREST studies and the results of registries in Europe and the US suggest that the Mitral clip procedure has a procedural success ( post procedural MR1 year.
Number of patients in the EVEREST trials and from ongoing registries suggests that percutaneous edge to edge mitral valve repair is feasible, at low procedural risk, in patients with secondary MR in the absence of severe tethering, and may provide short term improvement in functional condition and LV function. These findings have to be confirmed in larger series with longer follow up and a randomised design. Data on coronary sinus annuloplasty are limited and most initial devices have been withdrawn. Percutaneous intervention may be considered in severely symptomatic patients despite optimal medical management if the heart team consider that they are high risk or even contraindicated for surgery, and who have a life expectancy >1year.
FFR-THE ALL IN ONE APPROACH FOR MANAGING CORONARY ARTERY DISEASE
Dr. Narbeh Melikian, London, England
Multiple studies have shown that cardiac prognosis in patients with stable coronary disease (CAD) is dependent on the presence of myocardial ischemia and unrelated to the extent of epicardial stenosis. However, there is ongoing debate whether there exists an optimal functional test that can be used in all patient groups. Fractional Flow Reserve (FFR), a highly sensitive and specific index of myocardial ischemia, and has many properties to fulfil this role. FFR is derived independently in each epicardial vessel and thus remains diagnostically accurate in patients with multi-vessel and left main disease. It has a high spatial resolution and is not influenced by haemodynamic parameters. Furthermore, it is highly reproducible and the results not open to interpretation. Therefore, it has been suggested that FFR is the current « gold standard » functional test to accompany patients undergoing coronary angiography.
LONG-TERM RESULTS OF PULMONARY VEIN ISOLATION IN PATIENTS UNDERGOING MITRAL VALVE SURGERY IN NMMC
Drs. G.H. Heboyan, S.A. Aghabekyan, Yerevan, Armenia
Currently various surgical procedures to treat atrial fibrillation are available. As it is known, the « gold standard » is considered the Cox-Maze procedure. However, because of technical difficulties it is not widely used. Moreover, the finding of focal source of atrial fibrillation originating from pulmonary veins, served as a basis for the simple isolation of the pulmonary veins as an effective treatment for atrial fibrillation.
The study evaluated the results of simple pulmonary vein isolation (single circumferential incision) with the cut and sew technique in the patients with atrial fibrillation undergoing mitral valve surgery. Three hundred and nine consecutive patients with atrial fibrillation who underwent pulmonary vein isolation from 1998 to 2010 were included in the study and examined retrospectively at Nork-Marash Medical Center, Yerevan, Armenia.
According to the preliminary results of the study, at 8 years of follow-up sinus rhythm was restored in 80.5% of patients, and at 10 years of follow-up it was restored in 73.7% of patients.
The obtained results of pulmonary vein isolation were effective for sinus rhythm restoration. Therefore, the simple technique, which is less time-consuming and has similar effectiveness may be a preferable procedure. Current results may serve as a basis for further revealing the origin and mechanisms of atrial fibrillation, as well as propose the most effective method for atrial fibrillation elimination.
COMPARISON OF DOOR-TO-BALLOON TIME FOR PRIMARY PCI USING TRANSRADIAL VERSUS TRANSFEMORAL APPROACH IN ST-SEGMENT ELEVATION MYOCARDIAL INFARCTION (STEMI) PATIENTS: SINGLECENTER EXPERIENCE
Dr. Aram Nazaryan, Yerevan, Armenia
Background and purpose
The transradial approach is now accepted worldwide as an alternative access site that reduces bleeding complications in patients undergoing percutaneous coronary interventions (PCI). Patients with STsegment elevation myocardial infarction (STEMI) who undergo primary PCI present a particularly efficacious indication for the transradial approach due to the intensity of their anticoagulation. However, concerns regarding prolonged door-to-balloon time (D2BT) in gaining access have limited use.
This single-center retrospective study was performed to compare the door-toballoon time (D2BT), procedure time, fluoroscopy time, contrast volumes, major adverse cardiac events (MACE) at 1 month between transradial (TR) and transfemoral (TF) PCI in ST-segment-elevation myocardial infarction (STEMI).
Methods
A hundred sixty consecutive patients with STEMI undergoing primary PCI were studied. Patient were divided in two groups, Group I undergoing PCI transfemorally (TF) and Group II patients transradially (TR).Demographic data, door to balloon times, procedural variables, predischarge adverse cardiac events and 1 month follow up major adverse cardiac events (MACE) were recorded.
Results
The difference of D2BT in Group I compared with Group II was not statistically significant. Demographics, predischarge adverse events and MACE at 1 month follow up were comparable between the two groups.
Conclusions
Transradial approach to primary PCI provides similar door-toballoon times to transfemoral approach in patients with STEMI.