Transmitral Pressure Gradient Research Articles

Immediate and mid-term result of restrictive mitral annuloplasty using a small semi-rigid ring

Though annuloplasty using a properly sized ring has been advocated in degenerative mitral regurgitation, restrictive annuloplasty using a down-sized ring is widely used in ischemic mitral regurgitation. We investigated the outcome of restrictive annuloplasty using a small (24- or 26-mm) ring in mitral regurgitation irrespective of the etiology. Nineteen patients underwent a restrictive annuloplasty using a 24-mm (n = 8) or 26-mm (n = 11) semi-rigid ring. The etiology included degenerative in 13 patients, ischemic in 3, endocarditis in 2, and congenital in 1. Body surface area of the patients implanted with the 24-mm ring was 1.40 ± 0.16 and 1.60 ± 0.18 m(2) for the 26-mm ring. Fifteen patients had 3+ or 4+ mitral regurgitation preoperatively. Two patients were converted to valve replacement for residual mitral regurgitation during the operation. One operative mortality associated with infection was observed. Echocardiogram at 29.4 ± 14.2 months postoperatively demonstrated mitral valve area of 2.0 ± 0.6 cm(2) for 24-mm ring and 2.2 ± 0.5 cm(2) for 26-mm ring with indexed mitral valve area of 1.4 ± 0.4 cm(2)/m(2) for both groups, and no mitral regurgitation more than 2+. Transmitral mean pressure gradient on rest was 4.7 ± 2.1 mmHg at last follow up. New York Heart Association class improved from 2.2 ± 0.7 to 1.2 ± 0.2 after the operation. No late death or reoperation was observed during the follow-up of 31.0 ± 15.0 months. Restrictive mitral annuloplasty using a small ring provided acceptable early and midterm results in patients with body surface area around 1.5 cm(2) without Barlow pathology. Restrictive annuloplasty may be another technical aspect to avoid valve replacement.

PERCUTANEOUS TRANSMITRAL COMMISSUROTOMY (PTMC)

Background: Mitral stenosis is one of the grave consequences of rheumatic heart disease.Balloon valvuloplasty for stenosed mitral and pulmonary valves has been practiced with good results in theworld. Since Inoue et al. introduced balloon valvuloplasty in 1982, percutaneous transmitral commissurotomy(PTMC) has become the treatment of choice for mitral stenosis replacing surgical commissurotomy andmitral valve replacement in many cases. Objective: The aim of this study was to audit the proceduralsuccess, in hospital outcome in patients undergoing percutaneous trans-mitral balloon commissurotomy(PTMC) in our set up. Study Design: Observational cross sectional study. Place and Duration: The studywas conducted at Faisalabad Institute of Cardiology Faisalabad from March 2011 to December 2013.Materials and Methods: Total one hundred and twenty four patients underwent percutaneous transmitralcommissurotomy from March 2011 to December 2013. Any patient of age ≥ 10 years with mitral stenosiswho fulfills the inclusion and exclusion criteria for PTMC was enrolled in this study. A full history particularly,age, sex, occupation, address, symptoms regarding their referral for medical checkup was noted. Detailedclinical examination especially relevant cardiovascular examination of all the patients was done. ECG ofevery patient was done. Baseline routine investigations including blood complete with ESR, electrolytes,CRP, LFT, RFT was done in each case. A baseline echocardiography was performed in all patients. Mitralvalve area was calculated by planimetry and by pressure half time method. Severity of mitral stenosis wasgraded as: very sever stenosis (valve area <1cm2), severe (valve area 1- 1.5 cm 2) moderate (valve area1.5- 2 cm2) and mild (valve area > 2.0 cm2). To exclude any clot in LA and LA appendage Transesophagealechocardiography (TEE) was performed. In Cath Lab pre and post PTMC invasive hemodynamics includingLA, RA, RV, left ventricular end-diastolic pressure (LVEDP), and transmitral pressure gradient (PG) wascalculated. Those patients who have echo contrast on echocardiography were given 5000 IU heparinIV after septal puncture. Antibiotic prophylaxis was initiated in all patients thereafter. The procedure wasperformed under local anesthesia, if needed moderate sedation was given with midazolam. The procedurewas ended when either at least one commissure was splitted, adequate increase in mitral valve area orincrease in degree of MR or decrease in mean LA pressure to ½ of pre PTMC value or decrease in mitralvalve gradient was observed. After 24-48 hours patient was discharged and before discharge transthorasicecho was done to measure all the parameters as pre PTMC along with any echo finding of pericardialeffusion. Results: Total 124 patients were studied, 92(74.2%) were female and 32(25.8%) were maleshowing a female predominance. The mean age was 27.29±9.3. Most of the patients 58(46.8%) were inage group 21-30 years. 87(70.16%) patients were in atrial fibrillation and 37(29.83%) had sinus rhythm. Theprocedure was successful in 118(95.16%) patients. 2(1.6%) patients need urgent MVR due to severe MRand 1 (0.8%) died during procedure. Most of the patients 85(68.55%) were in NYHA class III. After PTMC,ASD was present in 13(10.5%) patients. After PTMC moderate MR was seen in 2(1.6%) and severe MR wasobserved in 4(2.173%) patients. Most of the patients 115(92.7%) before PTMC were in severe pulmonaryhypertension and after PTMC most of the patients 91(73.4%) were in mild pulmonary hypertension. PrePTMC mean MVA (cm2) was 0.684± 0.1226 and post PTMC it was 1.533± 0.281 cm2. Mean MVPG prePTMC was 26.178±5.94 mmHg and post PTMC it was 7.62±5.007 mmHg with significant p value 0.0001.Mean LA pressure before procedure was 29.68±8.137 mmHg and post PTMC it was 12.28±6.99 and pvalue was 0.0001. 10 patients had special problems, 3 had previous H/O PTMC, 3 were pregnant lady, onehas kyphoscoliosis, one had large IAS aneurysm, one had H/O CVA and one patient was suffering fromrenal cell carcinoma. Conclusions: The outcome of this study suggests that PTMC is a safe procedure inexperienced hand with good success rate and optimal results even in patients with special problems likepregnancy, previous CVA and redo cases.

Role of the Mitral Valve Resistance in Evaluation of Mitral Stenosis Severity

Background: Mitral valve resistance (MVR) is an important hemodynamic consequence of mitral stenosis (MS). We aimed to determine whether the mitral valve resistance could be used as a clinically reliable method for estimation of MS severity. Materials and Methods: Transthorathic echocardiographic study of 128 patients with rheumatic MS to estimate; mitral valve area (MVA); planimerty (2D) and pressure half time (PHT), mitral valve score (MVS), right ventricular systolic pressure (RVSP), mean transmitral pressure gradient (MPG), diastolic filling time (DFT), left ventricular out flow tract diameter (LVOTd) and velocity time integral (LVOT vti), MVR calculated as: MPG/aortic flow ratio [(LVOTd) (LVOTvti)/DFT] in dynes.sec.cm-5. Results: MVR at cut off values of: ≥105.26 dynes.sec.cm-5, had a sensitivity of 86.7% and a specificity of 74.5% for severe MS, between 76.02 and 105.26 dynes.sec/cm5 it had a sensitivity of 85.2% and a specificity of 72% for moderate MS, at ≤76.02 dynes.sec/cm5 it had a sensitivity of 81% and a specificity of 91% for mild MS. MVR in moderate MS; can detect symptomatic patients at a cut off value ≥85.65 dynes.sec/cm5 with a sensitivity of 87% and a specificity of 100%. MVR had positive correlations with MVS and RVSP (r=0.618 and 0.401), -ve correlations with MVA-2D and PHT (r=-0.559 and -0.284), P<0.01. MVR was an independent predictor of the NYHA functional class (B ± SE0.003 ± 0.001, odds ratio 0.3, P<0.01). NYHA functional class showed the best correlation with MVR (r=0.630, P<0.01). Conclusion: MVR can be used as a parameter for expression of stenosis severity, and could be used for evaluation of symptomatic moderate MS.

0582: Discordance between mitral valve area and mean transmitral pressure gradient in mitral stenosis: is mean gradient marker of the severity or parameter of tolerance in severe mitral stenosis?

Definition of objective criteria to conclude the severity of MS is still important. (1) to evaluate correlation between the mean transmitral gradient (MTG) and severity of MS in patients with a severe or very severe MS (2) To analyze the different parameters which determine the mean transmitral gradient. We conducted a prospective study including fifty patients admitted for severe or very severe MS, over a period of one year. We first studied the correlation between mitral valve area and MTG. Then we separately analyzed two groups of patients: those with a MTG <10mmHg (group 1) and those with a MTG>10mmHg (group2). We performed for each group an univariate correlation between MTG and dyspnea, heart rate, cardiac decompensation, regularity of rhythm, function of right ventricle and systolic pulmonary artery pressure (SPAP). 64% of our patients had a severe MS and 36% had a very severe MS. 52% had a MTG <10mmHg and 48% had a mean gradient>10mmHg; suggesting lack of correlation between the severity of MS and MTG (Pearson coefficient R: –0.137). Regarding dyspnea, 80% of patients in group 1 had a dyspnea stage II of NYHA and 70% of patients in group 2 had a dyspnea stage III (41%) or IV (29%). The analytical study of heart rate (HR) and the presence of cardiac decompensation compared with MTG showed a significant correlation. Among the patients in group 1, 96% had a HR between 60 and 100 bpm and no patient was in cardiac decompensation. In group 2, 54% (13 patients) had a HR >100 bpm and 7 of them (53%) were in left heart failure. The study of SPAP in the two groups found a statistically significant correlation between the SPAP and MTG. Mean transmitral gradient is a good indicator of the tolerance of mitral stenosis, but it reflects poorly severity because it depends on several hemodynamic parameters.

Abstract 15498: Partial Band Mitral Annuloplasty Can Preserve Mitral-aortic Valve Dynamic Coupling After Mitral Valve Repair in Comparison With Complete Ring Plasty

Introduction: The aortic and mitral valves (MV) demonstrate synchronous behavior to facilitate both left ventricular (LV) filling and emptying. Although partial band (PB) mitral annuloplasty is often performed to maintain anterior annulus flexibility, actual advantages remain undefined. The object of this study is to identify the effects of PB annuloplasty compared with complete ring (CR). Methods: We retrospectively evaluated 24 patients who underwent MV repair for degenerative mitral regurgitation. A PB (CG Future band, Medtronic Inc) was used in 13 patients and a CR (Carpentier-Edwards Physio or Physio II ring, Edwards Lifesciences) in 11. Three-dimensional transesophageal echocardiography was performed and 4D-MV Assessment, 2.0 (TomTec Imaging Systems) was used for semiautomatic tracking of mitral annulus (MA). Aortic annulus (AoA) was manually traced frame by frame in transverse plane perpendicular to LV outflow tract at the level of hinge points of sinuses, which was reconstructed from three-dimensional datasets. Results: MA surface and AoA projected areas changed reciprocally throughout cardiac cycle (Fig a and b). The PB orifice area measured in vitro was smaller than CR (4.8±0.9 vs 5.8±1.2 cm2, P&lt;0.05). There was no difference in patients’ body surface area (1.57±0.21 vs 1.67±0.20 m2). However, the MA area in PB constantly tended to be larger than in CR (maximum area: 8.1±2.0 vs 6.7±1.5 cm2, P=0.09, Fig a). In PB, MA surface area change was greater (10.1±6.0% vs 5.9±2.9%, P&lt;0.05: Fig c); consequently, AoA projected area change was much larger than in CR (39.2±11.0% vs 18.4±4.2%, P&lt;0.01: Fig d). Immediately postoperative residual regurgitation was none or of mild degree in all patients, and Doppler transmitral mean pressure gradient tended to be smaller in PB than in CR (2.0±0.4 vs 2.3±0.9 mmHg, P=0.32). Conclusions: PB mitral annuloplasty could preserve mitral-aortic dynamic coupling, which must provide important consideration at the time of MV repair.

Prevalence and clinical characteristics of degenerative mitral stenosis

BackgroundDegenerative mitral stenosis (DMS) is found in the elderly population. However, there are a few reports regarding the prevalence rate of DMS and, its clinical characteristics. The aim of this study was to determine the relationship between age, gender, and the prevalence rate of DMS. MethodsPatients with DMS and rheumatic mitral stenosis (RMS) were searched retrospectively in consecutive patients who underwent echocardiography from January 2011 to December 2013 in a community hospital. DMS was defined as presence of both turbulent antegrade flow with a mean transmitral pressure gradient (PG) of ≥2mmHg and mitral annular calcification without restriction of leaflets tip motion. ResultsWe identified 19 patients (17 female and 2 male) with DMS (0.22%) and 19 patients with RMS in 8683 patients. The prevalence rate of DMS significantly increased with aging, especially in patients >90 years old. There was no significant difference in the prevalence rates of RMS among the age groups. Patients with DMS were older (86±8 years vs. 73±10 years, p<0.01) and had higher rates of hypertension and aortic stenosis, larger left ventricular mass index, and mean PG of aortic valve, smaller aortic valve area, less degree of left atrial dilatation, and lower rate of atrial fibrillation, compared with those values in patients with RMS. ConclusionsDMS is rare (0.22%) and almost exclusively found in females in routine echocardiography. The prevalence of DMS increases with aging to 2.5% in patients >90 years of age, and DMS is often associated with aortic valve stenosis.

Prosthesis–patient mismatch due to small ring annuloplasty in patients with degenerative mitral insufficiency

BackgroundAvoidance of prosthesis–patient mismatch (PPM) is important when selecting a mitral valve prosthesis. This study investigated the effect of PPM after small ring mitral valve annuloplasty on postoperative hemodynamics and the clinical course. MethodsThis study retrospectively reviewed 227 patients with symptomatic severe mitral insufficiency (MI) who underwent mitral valve repair for degenerative MI using an Edwards ring or band (size: 26–32mm) between 2003 and 2012. Echocardiography was performed postoperatively and at follow-up to evaluate cardiac function, including residual MI, mean transmitral pressure gradient, left atrial diameter (LAD), and tricuspid regurgitant pressure gradient (TRPG). ResultsThere were no operative deaths. Actuarial freedom from major adverse cardiac events was 91% at 10 years. The postoperative MI grade was not significantly different between different sizes of prosthesis (26mm, 0.67±0.8; 28mm, 0.73±0.9; 30mm, 0.85±0.9; 32mm, 0.3±0.6). LAD and TRPG were significantly lower for each size of prosthesis at follow-up (all p<0.05). Patients with a smaller body surface area received a significantly smaller prosthesis (p<0.05). The transmitral pressure gradient was significantly higher in patients with a 26-mm prosthesis than in patients with a larger size of prosthesis. Thirty-three patients had a follow-up transmitral pressure gradient ≥5mmHg. The follow-up LAD was larger in patients with a transmitral pressure gradient <5mmHg than in patients with that ≥5mmHg (43.2±9.4mm vs 47.1±9.6mm, p<0.05). ConclusionsMitral valve repair results in excellent clinical outcomes with significant reductions in MI, LAD, and TRPG for all sizes of prosthesis. However, use of a smaller prosthesis may result in a higher mean transmitral pressure gradient, and may inhibit reverse remodeling of the left atrium. Therefore, PPM should be avoided.

The Influence of Mitral Annuloplasty on Left Ventricular Flow Dynamics

Mitral valve (MV) repair using annuloplasty rings is the preferred method of treatment for MV regurgitation, but the impact of annuloplasty ring placement on left ventricular intraventricular flow has not been studied. Annuloplasty rings of varying sizes were placed in 5 healthy sheep (intercommissural ring sizes were 24, 26, 28, 30, and 32 mm), and three-dimensional phase contrast magnetic resonance imaging (4D flow MRI) was performed before and 1 week after ring placement. Normal diastolic flow consisted of diastolic intraventricular vortices that naturally unwound during systole. Postsurgical intraventricular flow was highly disturbed in all sheep, and the disturbance was greatest for undersized rings. Ring size was highly correlated with the diastolic inflow angle (Pearson's r = -0.62, p < 0.1, 95% confidence interval: -0.92 to 0.14). There was a mean angle increase of mean diastolic inflow angle increase of 12.3 degrees (< 30 mm, p < 0.01, 95% confidence interval: 4.8 to 19.6) for rings less than 30 mm. There was an inverse relationship between peak velocity and annuloplasty ring area (Pearson's r = -0.80, p < 0.05, 95% confidence interval: -0.96 to -0.2). Transmitral pressure gradients increased significantly from baseline 0.73 ± 0.18 mm Hg to after annuloplasty 2.31 ± 1.04 mm Hg (p < 0.05). Mitral valve annuloplasty ring placement disturbs normal left ventricular intraventricular flow patterns, and the degree of disturbance is closely associated with annuloplasty ring size.

0359: Percutaneous balloon mitral commissurotomy in children and young adults with rheumatic mitral stenosis

To determine the efficacy and the safety of percutaneous balloonmitral commissurotomy (PBMC) in young patients (aged under 18 years – olds) with rheumatic mitral stenosis and to compare these results with those of adult patients. Percutaneous transvenous mitral commissurotomy (PTMC) using the Inoue technique was performed in 480 patients with rheumatic mitral stenosisbetween 1998 and 2013. 41 were aged under 18 years – old (group 1). The other 439 patients (group 2) had a mean age of 34±11.9 years. All patients were assessed clinically. An echocardiography was performed before and after the procedure. Mean age in group 1 was 15±2.95 years (range 8 to 18) with a women predominance (73.2% vs. 26.8%.). In group 1, there was a significant increase of the mean mitral valve area index (MVAI) (0.84±0.24 vs 1.78±0.39cm 2 , p <0.001), a significant reduction of the mean transmitral pressure gradient (21.78±6.62to8.75±5.87 mm Hg, p <0.001) and of the mean left atrial pressure (28.46±7.59to12.87±5.57 mmHg, p < 0,001) from pre- to post-PBMC, respectively. Mild mitral regurgitation developed in 12 and moderate mitral regurgitation developed in 3 patients.The mean follow-up was 92±40 months. Improvement in symptomatic status by at least one NYHA class was seen in the majority of patients.A good result during the follow up was observed in 46.3% of controlled patients and restenosis in 53.7% of cases with an average of 46±34 months. The immediate hemodynamic results in children were compared to 439 adult patients who underwent PBMC in the same period. The outcome was similar in both groups. Children were found to have significantly higher rate of mitral restenosis compared to adults (53.7% vs. 31.9%). Despite a high rate of restenosis, PBMC is very effective and safe in children, and consider that it should be the procedure of choice for young patients with symptomatic rheumatic mitral stenosis.

Clinical Outcomes of Mitral Valve Replacement With the 16-mm ATS Advanced Performance Valve in Neonates and Infants

Although mitral valve repair is the preferred treatment for mitral regurgitation in neonates and infants, mitral valve replacement (MVR) is sometimes necessary. From 1999 through 2013, 18 patients younger than 1 year underwent MVR with the smallest (16 mm) commercially available mechanical valve. At surgery, mean age was 4.0 ± 1.8 months (range, 4 days to 7 months), and mean body weight was 5.3 ± 1.6 kg (range, 3.2 to 8.3 kg). Prosthetic valves were implanted in the supra-annular position in 17 of the 18 patients. All patients were followed up, and the mean follow-up period was 4.5 ± 3.8 years (range, 0.2 to 14 years). The rates of overall survival and freedom from redo MVR at 10 years were 88.9% and 57.8%, respectively. The causes of redo MVR were pulmonary hypertension in patients with left ventricular outflow obstruction (n = 2), hemolysis (n = 1), and a stuck valve (n = 1). The estimated effective orifice area index (effective orifice area/body surface area) was significantly inversely correlated with peak transmitral pressure gradient (r = -0.784, p < 0.01). The rate of freedom from permanent pacemaker implantation at 10 years was 71.2%. Three of the 5 pacemaker implantation procedures were for postoperative sick sinus syndrome. Although intracranial hemorrhage developed in 3 infants, all neurologic sequelae resolved. The implanted valves were durable, and no premature increase in transmitral pressure gradient was observed. Complications included injury of the sinus node artery and hemorrhage related to anticoagulation therapy.

Abstract 19359: A Novel Parameter to Predict Long-term Cardiac Mortality in Mitral Stenosis

The prognosis of patients with mitral stenosis (MS) depends on the severity of obstruction and hemodynamic burden affecting the pulmonary vasculature. Net atrioventricular compliance (C n ) reflects the overall adverse hemodynamic consequence of MS and may be useful in predicting mortality. Methods: A total of 402 MS patients (mean age 51 ± 16 years, valve area of 1.04 ± 0.24 cm 2 , 84% female) undergoing percutaneous mitral valvuloplasty (PMV) between 2000 and 2013 at 2 centers were enrolled. Invasive hemodynamic and echocardiographic measures (pre and 24 hours post PMV) were examined and patients were followed for a median of 28 months post PMV. Endpoints were cardiovascular death (primary), and a composite of death from any cause, mitral valve replacement (MVR) or repeat PMV (secondary). Results: At baseline, 138 (34%) were in atrial fibrillation and 48% were NYHA functional class III or IV. PMV resulted in significant increase in valve area, decrease in transmitral pressure gradients, pulmonary pressures and an improvement in right ventricular (RV) function. A total of 47 (12%) died (39 cardiovascular deaths). In addition, 48 patients underwent MVR, and 12 required repeat PMV with an overall incidence of adverse events of 11.4 events per 100 patient-years. Baseline C n was a strong predictor of both cardiac death (adjusted hazard ratio [HR] 0.69, 95% confidence interval [CI] 0.49 - 0.86, p = 0.008), and composite endpoint (adjusted HR 0.81, 95% CI 0.67 - 0.91, p = 0.016). Cardiac mortality was significantly higher in patients with C n ≤ 4 ml/mmHg than in patients with C n &gt; 4 ml/mmHg (adjusted HR 0.35, 95% CI 0.16 - 0.75, p=0.007), after adjusting for clinical factors, pulmonary artery pressure, tricuspid regurgitation (TR) severity, RV function and immediate procedural results. Survival rate at 1-, 3- and 5-years follow-up was 96%, 94% and 87% in patients with C n &gt; 4 ml/mmHg compared to 89%, 79% and 75% in patients with C n ≤ 4 ml/mmHg. Conclusions: Baseline C n is a strong predictor of cardiovascular-related mortality in patients with significant MS, after adjustment for other prognostic factors including postprocedural pulmonary artery pressure. C n assessment therefore has potential value in evaluation of mortality risk in the setting of MS.

Controversy in mitral valve repair, resection or chordal replacement?

Mitral valve plasty has superseded valve replacement as the standard technique for treating degenerative mitral valve prolapse. Quadrangular resection is considered the gold standard for posterior leaflet prolapse. Chordal replacement was first developed to treat the anterior leaflet and subsequently became widely used for the posterior leaflet, after which a new version of posterior leaflet resection was developed that did not involve local annular plication. In the era of the mini-thoracotomy, the premeasured loop technique is simple to adopt and is as durable as quadrangular resection. However, there is controversy surrounding whether resection or chordal replacement is the optimal technique. The resection technique is curative because it removes the main pathologic lesion. The disadvantage of the resection is that it can be complicated and often requires advanced surgical skills. In contrast, chordal replacement is not pathologically curative because it leaves behind a redundant leaflet. However, the long-term results appear to be equivalent in many reports. Functionally, chordal replacement retains greater posterior leaflet motion with a lower trans-mitral pressure gradient than quadrangular resection. Moreover, chordal replacement is simple and yields uniform results. The optimal technique depends on whether the anterior leaflet or posterior leaflet is involved, the Barlow or non-Barlow disease state, and whether a mini-thoracotomy or standard sternotomy approach is used. For mitral valve repair, the most superior and reliable technique for the posterior leaflet is resection using the newer resection technique with a sternotomy approach, which requires a skilled surgeon.

MitraClip Therapy in Surgical High-Risk Patients: Identification of Echocardiographic Variables Affecting Acute Procedural Outcome

The aim of the study was to assess predictors of acute procedural failure in surgical high-risk patients undergoing MitraClip (Abbott Vascular, Abbott Park, Illinois) therapy. MitraClip implantation is a novel percutaneous option to treat significant mitral regurgitation (MR). In 300 patients (75 ± 9 years of age, 190 [63%] men), of whom 32 (10.7%) had been unsuccessfully treated (discharge MR grade of >2+), baseline clinical and echocardiographic variables were evaluated by exact logistic regression and classification tree analyses to assess their impact on acute procedural failure. Acute procedural failure was differentiated into aborted procedure (no MitraClip implanted; n = 11) and "clip failure" (inadequate MR reduction despite MitraClip implantation; n = 21). Multivariate logistic regression identified effective regurgitant orifice area (EROA), mitral valve orifice area (MVOA), and mean transmitral pressure gradient (TMPG) as independent predictors of overall acute procedural failure. Classification tree analysis revealed that an EROA >70.8 mm(2) (n = 28) was associated with a high rate (25%) of clip failures, whereas the combination of an MVOA ≤3.0 cm(2) and a TMPG ≥4 mm Hg (n = 16) was associated with a high rate (37.5%) of aborted procedures. Failure rates of ≤10% were observed in all patients with an EROA ≤70.8 mm(2) and either an MVOA >3.0 cm(2) (n = 217) or an MVOA ≤3.0 cm(2) in concert with a TMPG ≤3 mm Hg (n = 39). Multinomial logistic regression identified an EROA >70.8 mm(2) and a TMPG ≥4 mm Hg as independently predictive of clip failure, but an MVOA ≤3.0 cm(2) and a TMPG ≥4 mm Hg as independently predictive of procedure abortion. In surgical high-risk patients undergoing MitraClip therapy, a TMPG ≥4 mm Hg, an EROA ≥70.8 mm(2), and an MVOA ≤3.0 cm(2) carry an increased risk of procedural failure.

Echocardiographic Predictors of Left Atrial Thrombus in Patients With Severe Rheumatismal Mitral Stenosis

Background: Rheumatismal mitral stenosis is less common today than it was several decades ago, but it is a common cause of mitral stenosis (MS) in the developing world. Mitral valve stenosis symptoms include fatigue, palpitations, and Shortness of breath especially with exertion. Objectives: The purpose of this prospective study was to determine the incidence of left atrial (LA) thrombus and the predisposing factors predicting its developments in patients with symptomatic rheumatismal mitral stenosis who underwent transesophageal echocardiography (TEE) planed for percutaneous transvenous mitral commissurotomy (PTMC). Patients and Methods: Patients who were referred to perform TEE before mitral balloon valvuloplasty enrolled the study. Data were analyzed by SPSS. Results: Out of 92 patients, females were 68 (73.91%). Mean age was 43.35 ± 13.94. They were classified into two groups based on the presence or absence of LA thrombus. Group A consisted of 21 patients (seven men and 14 women) with LA thrombus (mean age of 53.00 ± 15.70 years). Group B consisted of 71 patients (17 men and 54 women) without LA thrombus. There were no statistically significant differences between the two groups regarding age, sex, LA diameter, LA area, LA smoke, Trans-mitral mean pressure gradient, systolic pulmonary artery pressure, left ventricular ejection fraction and right ventricular function, but patients with LA clot had more LA appendage dysfunction, more frequent atrial fibrillation rhythm, and smaller mitral valve area (P = 0.020, 0.005 and 0.020 respectively) and the prevalence of MR was also lower in this group (P = 0.049). In our evaluation there was no statistically significant difference regarding the LA diameter or LA area in patients with or without LA smoke. Conclusions: The frequency of left atrial clots increased with the presence of LAA dysfunction, atrial fibrillation rhythm, and smaller mitral valve area. Presence of MR had protective effects against LA clots.

Impact of prosthesis-patient mismatch on late recurrence of atrial fibrillation after cryomaze procedure with mitral valve replacement.

This study investigated the impact of prosthesis-patient mismatch (PPM) after mitral valve replacement (MVR) with cryoablation using a maze procedure. We evaluated 142 patients who underwent MVR with a cryomaze procedure. Echocardiography was performed at 1 week and at 1, 3, 5, 7, and 10 years. An effective orifice area index of 1.2 cm(2)/m(2)was used to define PPM. Mean transmitral pressure gradient (mean MPG) >5 mmHg was defined as high. PPM was a risk for overall mortality and a predictor of admission for heart failure. Mean MPG at 1 week was significantly higher in PPM patients (4.8 ± 1.5 mmHg vs. 3.7 ± 1.2 mmHg, P<0.001). Left atrium (LA) dimension decreased after the operation and did not change in patients without high mean MPG, while it increased after 7 years in patients with high mean MPG. The significant predictor of AF recurrence after 1 year was LA dimension ≥ 52.9 mm. Yearly AF recurrence was 10.6% in patients with LA dimension ≥ 52.9 mm, and 1.8% in the others. In patients with high mean MPG, tricuspid regurgitation pressure gradient (TRPG), related to pulmonary artery pressure, was increased after 7 years. PPM is a risk for late mortality, admission for heart failure, and high mean MPG, while the last was related to risk of enlargement of LA and increase of TRPG after 7 years. LA dimension after surgery is a predictor of late recurrence of AF, especially when ≥ 52.9 mm.

Value of the Mitral Valve Resistance in Evaluation of Symptomatic Patients with Mild and Moderate Mitral Stenosis – A Dobutamine Stress Echocardiographic Study

Conventional stenosis indexes poorly reflect the major hemodynamic consequence of mitral stenosis (MS). Valve resistance (VR) is a physiologic expression of stenosis. This study aimed to demonstrate whether the mitral valve resistance (MVR) and its changes, relate to restricted exercise capacity in patients with mild and moderate mitral stenosis. Twenty-four patients with rheumatic mild-to-moderate MS underwent transthoracic echocardiographic study (resting and dobutamine stress echocardiography [DSE]), divided into two groups; group I: symptomatic (12 patients) and group II: asymptomatic (12 patients). Mitral valve area (MVA), mean transmitral diastolic pressure gradient (TMPG), cardiac output (CO), and MVR were measured in all patients at rest and at peak DSE. Changes (∆) in MVA, TMPG, CO, and MVR were calculated. Data underwent statistical analysis. From resting to peak dobutamine infusion, the MVR significantly decreased from 111.4 ± 28.2 to 83.6 ± 27.0 dynes sec/cm(5) in group II (P < 0.001). The increase in MVR in group I (13.8 ± 10.3 dynes sec/cm(5)) compared with its reduction (-27.8 ± 15.6 dynes sec/cm(5)) in group II were highly significant different (P < 0.001). A reduction in MVR by less than 21.5 dynes sec/cm(5) at peak dobutamine infusion reflect a cutoff value considered to detect the hemodynamic significance of mild-to-moderate MS with a sensitivity of 92% and a specificity of 73%. The changes in the MVR can be used as a DSE parameter for expression of stenosis severity and to describe discrepancy in symptom status in patients with mild-to-moderate mitral stenosis.

Intraoperative Evaluation of Transmitral Pressure Gradients after Edge-to-Edge Mitral Valve Repair

ObjectiveEdge-to-edge repair of the mitral valve (MV) has been described as a viable option used for the surgical management of mitral regurgitation (MR). Based on the significant changes in MV geometry associated with this technique, we hypothesized that edge-to-edge MV repairs are associated with higher intraoperative transmitral pressure gradients (TMPG) compared to conventional methods.MethodsPatient records and intraoperative transesophageal echocardiography (TEE) examinations of 552 consecutive patients undergoing MV repair at a single institution over a three year period were assessed. After separation from cardiopulmonary bypass (CPB), peak and mean TMPG were recorded for each patient and subsequently analyzed.Results84 patients (15%) underwent edge-to-edge MV repair. Peak and mean TMPG were significantly higher compared to gradients in patients undergoing conventional repairs: 10.7±0.5 mmHg vs 7.1±0.2 mmHg; P<0.0001 and 4.3±0.2 mmHg vs 2.8±0.1 mmHg; P<0.0001. Only patients with mean TMPG ≥7 mmHg (n = 9) required prompt reoperation for iatrogenic mitral stenosis (MS). No differences in peak and mean TMPG were observed among edge-to-edge repairs performed in isolation, compared to those performed in combination with annuloplasty: 11.0±0.7 mmHg vs 10.3±0.6 mmHg and 4.4±0.3 mmHg vs 4.3±0.3 mmHg. There were no differences in TMPG between various types of annuloplasty techniques used in combination with the edge-to-edge repairs.ConclusionsEdge-to-edge MV repairs are associated with higher intraoperative peak and mean TMPG after separation from CPB compared to conventional repair techniques. Unless gradients are severely elevated, these findings are not necessarily suggestive of iatrogenic MS. Thus, in the immediate postoperative period mildly elevated TMPG can be expected and tolerated after edge-to-edge mitral repairs.

GW24-e2470 Safety and efficacy of percutaueous balloon mitral valvuloplasty in patients with mitral stenosis and thrombus in the left atrial appendage after thrombolytic and anticoagulation therapy

ObjectivesTo evaluate the safety and efficacy of percutaueous balloon mitral valvuloplasty (PBMV) in patients with mitral stenosis and thrombus in the left atrial appendage after thrombolytic and anticoagulation therapy.Methods25 patients,...

In Vitro Comparison of Doppler and Catheter-Measured Pressure Gradients in 3D Models of Mitral Valve Calcification

Mitral annular calcification (MAC) involves calcium deposition in the fibrous annulus supporting the mitral valve (MV). When calcification extends onto the leaflets, valve opening can be restricted. The influence of MAC MV geometry on Doppler gradients is unknown. This study describes a novel methodology to rapid-prototype subject-specific MAC MVs. Replicated valves were used to assess the effects of distorted annular-leaflet geometry on Doppler-derived, transmitral gradients in comparison to direct pressure measurements and to determine if transmitral gradients vary according to measurement location. Three-dimensional echocardiography data sets were selected for two MAC MVs and one healthy MV. These MVs were segmented and rapid prototyped in their middiastolic configuration for in vitro testing. The effects of MV geometry, measurement modality, and measurement location on transmitral pressure gradient were assessed by Doppler and catheter at three locations along the MV's intercommissural axis. When comparing dimensions of the rapid-prototyped valves to the subject echocardiography data sets, mean relative errors ranged from 6.2% to 35%. For the evaluated MVs, Doppler pressure gradients exhibited good agreement with catheter-measured gradients at a variety of flow rates, though with slight systematic overestimation in the recreated MAC valves. For all of the tested MVs, measuring the transmitral pressure gradient at differing valve orifice positions had minimal impact on observed gradients. Upon the testing of additional normal and calcific MVs, these data may contribute to an improved clinical understanding of MAC-related mitral stenosis. Moreover, they provide the ability to statistically evaluate between measurement locations, flow rates, and valve geometries for Doppler-derived pressure gradients. Determining these end points will contribute to greater clinical understanding for the diagnosis MAC patients and understanding the use and application of Doppler echocardiography to estimate transmitral pressure gradients.

Mitral valve repair using multiple MitraClips®: a dobutamine stress echocardiography evaluation

The haemodynamic effect of mitral valve (MV) repair using multiple MitraClips® (MC) has not been investigated. The aim of the study was to evaluate the stress performance of MV repair with MC. Twenty consecutive patients (77±7 years, 13 men [65%]) after implantation of >2 MitraClips® were subsequently evaluated with dobutamine stress echocardiography (DSE). After MC implantation, mean transmitral pressure gradient (TPG) (3.3±0.8 mmHg vs. 4.0±0.6 mmHg; p<0.001) and mitral valve orifice area (2.9±0.3 cm2 vs. 3.9±0.4 cm2; p<0.001) were significantly increased during DSE showing a physiological behaviour effect of the MV. LVEF (41±18% vs. 46±21%; p<0.001) and systolic pulmonary artery pressure (42±11 mmHg vs. 44±12 mmHg; p=0.014) increased significantly. The degree of MR was stable during stress (p=0.68). At linear regression, only baseline peak TPG was related to stress mean TPG (p<0.001; Beta 0.816; 95% CI: 0.368-0.918). MV repair using MitraClips® should be performed with the aim of maximal reduction of MR degree. MV repair using MC may not lead to pathological degrees of MV stenosis. Although the TPG is significantly increased during stress, it never reaches pathological levels and is always accompanied by a significant increase in MVOA. The degree of residual MR remains unchanged during maximal pharmacological stress.