Assessment of mitral valve reserve capacity before and after percutaneous balloon valvuloplasty with isoproterenol stress echocardiography

Objective: To explore whether successful valvuloplasty increases mitral valve reserve capacity in patients with mitral stenosis. Methods: Thirty-eight patients with pure rheumatic mitral stenosis underwent isoproterenol stress echocardiography before and after successful percutaneous balloon valvuloplasty. The mitral valve area (by direct planimetry of two-dimensional echocardiography), mean transmitral pressure gradient (by continuous-wave Doppler echocardiography), and cardiac output (by M-mode echocardiography) were measured at rest and under isoproterenol infusion to achieve heart rate of different stages. Results:Between the measurements before and after valvuloplasty, significant differences were observed in the mitral valve area (0. 91±0. 28 vs 1. 87±0. 23 cm2, P<0. 01), mean transmitral pressure gradient (12. 5±6. 3 vs 3. 9±1. 9 mmHg, P<0. 01) and cardiac output (3. 93±1. 44 vs 4. 73±1. 01 L/min, P<0. 05) at rest. Before valvuloplasty, the mean transmitral pressure gradient increased significantly (P<0. 01) as heart rate increased, but there were no significant differences in the measurements of mitral valve area and cardiac output (both P>0. 05). In contrast, there was a significant increase after valvuloplasty in the mean transmitral pressure gradient (P<0. 01), but both mitral valve area and cardiac output further increased (both P< 0. 01) as heart rate increased. Moreover, valvuloplasty decreased the mean transmitral pressure gradient at peak heart rate from 23. 0±4. 5 to 7. 75±2. 30 mmHg (F<0. 01) under submaximal stress. Conclusion: Successful percutaneous balloon valvuloplasty soon causes a significant increase of mitral valve reserve capacity in patients with mitral stenosis, which is conspicuously manifested under condition of hemodynamic stress. Stress echocardiography provides a safe, feasible and non-invasive means of assessing the reserve capacity.

Isoproterenol Stress Echocardiography in Assessing Mitral Valve Area Reserve before and after Percutaneous Balloon Valvuloplasty

Objective To determinewhether successful valvuloplasty causes an increase of mitral valve area reserve in patients with mitral stenosis, isoproterenol stress echocardiography was used to compare mitral valve area and hemodynamic changes between pre - and post - valvuloplasty under conditions of increased cardiac work. Methods Thirty-eight patients with pure rheumatic mitral stenosis who had received successful percutaneous balloon valvuloplasty underwent isoproterenol stress echocardiography pre- and post - valvuloplasty. Mitral valve area (by direct planimetry of two - dimensional echocardiography), mean transmitral pressure gradient (by continuous-wave Doppler echocardiography), and cardiac output (by M-mode echocardiography) were measured at rest and under isoproterenol stress to achieve heart rate of different stages. Results Mitral valve area (0.91±0.28 to 1.87±0.23 cm2, P<0. 01), mean transmitral pressure gradient (12. 5±6. 3 to 3. 9± 1. 9 mmHg, P < 0. 01) and cardiac output (3. 93± 1. 44 to 4. 73±1. 01 L/min, P < 0. 05) at rest between pre - and post - valvuloplasty were significantly different. Pre - valvuloplasty, as heart rate increased under stress, mean transmitral pressure gradient increased significantly ( P < 0. 01), but there were no significant differences in the measurements of mitral valve area and cardiac output (both P>0. 05) . In contrast, as heart rate increased post-valvuloplasty, there was a significant increase in mean transmitral pressure gradient (P<0.01), but both mitral valve area and cardiac output further increased significantly (bothP<0. 01) . Moreover, valvuloplasty decreased mean transmitral pressure gradient at peak heart rate from 23. 0±4. 5 to 7. 75 ± 2. 30 mmHg ( P < 0. 01) under submaximal stress. Conclusions Successful percutaneous balloon valvuloplasty soon causes a significant increase of mitral valve area reserve in patients with mitral stenosis, which is markedly manifested under conditions of hemodynamic stress. Stress echocardiog-raphy provides a safe, feasible and non-invasive means of assessing this reserve capacity.

Hypercoagulability existing in the local left atrium of patient with mitral stenosis

Objective To investigate the pathogenesis of thromboembolism in patients with mitral stenosis in a pre-thrombotic state.Methods The biochemical markers’ levels in plasma for platelet activity [soluble P-selectin (GMP-140)],states of thrombin generation [antithrombin Ⅲ (AT Ⅲ) and protein C (PC)],fibrinolysis [D-dimer (DD), plasminogen activator inhibitor 1 (PAI-1),tissue plasminogen activator (t-PA) and FDP] and von Willebrand factor (vWF) were determined from blood specimens obtained from the femoral veins and arteries and the right and left atria of 43 consecutive patients (20 with atrial fibrillation and 23 with sinus rhythm) with mitral stenosis (MS),undergoing percutaneous mitral valvuloplasty. The same parameters were compared with those of 15 control subjects,who had no detectable heart disease,but with paroxysmal supraventricular tachycardia undergoing radiofrequency catheter ablation of the left accessory pathway through a transseptal passage. Results Blood from the left atrium contained an excessive amount of platelet activity,thrombin generation and fibrinolysis compared with the blood from the right atrium,and the femoral veins and arteries. However blood from the right atrium was much lower in these activities when compared with those from the left atrium,and the femoral veins and arteries in both groups. Compared with those in the control subjects, GMP-140 in the left atrium was significantly higher ( P <0.05) and AT Ⅲ was significantly lower ( P <0.05) in patients with MS. Compared with the patients with MS and spontaneous left atrial echocontrast (LASEC)≤1,the patients with MS and LASEC≥2 had significantly higher levels of GMP-140 in plasma ( P <0.05),and significantly lower levels of AT Ⅲ ( P <0.05) and PC ( P <0.01) levels in the left atrium. However, there were no significant differences between patients with atrial fibrillation and those with sinus rhythm regarding amounts of plasma coagulation markers in the left atrium. Univariate regression analysis revealed that LASEC was negatively correlated with plasma levels of blood from the left atria in the patients with MS. Conclusion Coagulability is increased in the left atria of patients with MS and is positively correlated with LASEC.

Left atrial appendage flow velocity in rheumatic mitral stenosis

The left atrial appendage ( LAA ) has been considered a relatively insignificant portion of the cardiac anatomy. Because thrombi have been found to have a predilection to form within the LAA, a better understanding of the LAA is necessary. Transesophageal echocardiography (TEE) is a technique that makes clear imaging of the

Assessment of right ventricular function for patients with rheumatic mitral stenosis by 64-slice multi-detector row computed tomography： comparison with magnetic resonance imaging

Background Right ventricular （RV） dysfunction ensues due to rheumatic mitral stenosis （RMS）. The evaluation of RV function is clinically important for the diagnosis, treatment, and follow-up for patients with different degrees of RMS. The purpose of this study was to determine whether the 64-slice multi-detector row computed tomography （64-slice MDCT） can assess the RV function in RMS with high accuracy and reproducibility when compared to MR imaging （MRI）. Methods Right ventricular end-diastolic and end-systolic volumes （RV-EDV and RV-ESV）, stroke volume （RV-SV）, ejection fraction （RV-EF）, cardiac output （RV-CO）, and wall mass （RV-Mass） were measured with dedicated cardiac analysis software on 64-slice MDCT and compared with values measured with MRI in 43 consecutive patients with RMS. Agreement between MRI and 64-MDCT results were compared with Bland and Altman analysis and linear regression analysis. Repeated measurements were performed to determine intraobserver and interobserver variability. Results No significant differences were revealed in calculated RV function parameters between the two methods. RV-EDV, RV-ESV, RV-SV, RV-EF, RV-CO, and RV-Mass by 64-slice MDCT were similar to those by MRI （P〉0.05）. There were good correlations （r=0.98, 0.97, 0.96, 0.96, 0.95 and 0.77, respectively） and close agreement （bias=-0.2 ml, -1.0 ml, 0.8 ml, 0.5%, 26.1 ml, and 0.5 g, respectively, P〉0.05）. The variability in 64-slice MDCT measurements was similar to that in MRI values. Conclusion ECG-gated 64-slice MDCT could assess the RV function in RMS with high accuracy and reproducibility when com~）ared to MRI.

Application of Percutaneous Balloon Mitral Valvuloplasty in Patients of Rheumatic Heart Disease Mitral Stenosis Combined with Tricuspid Regurgitation

Background： Tricuspid regurgitation （TR） is frequently associated with severe mitral stenosis （MS）, the importance of significant TR was often neglected. However, TR influences the outcome of patients. The aim of this study was to investigate the efficacy and safety of percutaneous balloon mitral valvuloplasty （PBMV） procedure in rheumatic heart disease patients with mitral valve （MV） stenosis and tricuspid valve regurgitation. Methods： Two hundred and twenty patients were enrolled in this study due to rheumatic heart disease with MS combined with TR. Mitral balloon catheter made in China was used to expand MV. The following parameters were measured before and after PBMV： MV area （MVA）, TR area （TRA）, atrial pressure and diameter, and pulmonary artery pressure （PAP）. The patients were followed for 6 months to 9 years. Results： After PBMV, the MVAs increased significantly （1.7 ± 0.3 cm2 vs. 0.9 ± 0.3 cm2, P 〈 0.01）; TRA significantly decreased （6.3 ± 1.7 cm2 vs. 14.2 ± 6.5 cm2, P 〈 0.01）, right atrial area （RAA） decreased significantly （21,5 ± 4.5 cm2 vs. 25.4 ± 4.3 cm〈 P 〈 0.05）, TRA/RAA （%） decreased significantly （29.3 ± 3.2% vs. 44.2 ± 3.6%, P 〈 0.01）. TR velocity （TRV） and TR continue time （TRT） as well as TRV - TRT decreased significantly （ 183.4± 9.4 cm/s vs. 254.5 ± 10.7 cm/s, P 〈 0.01 ; 185.7 ± 13.6 ms vs. 238.6 ±l 1.3 ms, P 〈 0.01 ; 34.2 ±5.6 cm vs. 60.7 ± 8.5 cm, P 〈 0.01, respectively）, The postoperative left atrial diameter （LAD） significantly reduced （41.3 ± 6.2 mm vs. 49.8± 6.8 mm, P 〈 0.01） and the postoperative right atrial diameter （RAD） significantly reduced （28.7 ±5.6 mm vs. 46.5 ± 6.3 mm, P 〈 0.01 ）; the postoperative left atrium pressure significantly reduced （ 15.6 ± 6.1 mmHg vs. 26.5 ± 6.6 mmHg, P 〈 0.01 ）, the postoperative right atrial pressure decreased significantly （ 13.2 ±2.4 mmHg vs. 18.5 ±4.3 mmHg, P 〈 0.01 ）. The pulmonary arterial pressure decreased significantly after PBMV （48.2 ± 10.3 mmHg vs. 60.6 ±15.5 mmHg, P 〈 0.01）. The symptom of chest tightness and short of breath obviously alleviated. All cases followed-up for 6 months to 9 years （average 75± 32 months）, 2 patients with severe regurgitation died （1 case of massive cerebral infarction, and 1 case of heart failure after 6 years and 8 years, respectively）, 2 cases lost access. At the end of follow-up, MVA has been reduced compared with the postoperative （1.4 ± 0.4 cm2 vs. 1.7 ±0.3 cm2, P 〈 0.05）; LAD slightly increased compared with the postoperative （45.2 ± 5.7 mm vs. 41.4 ± 6.3 mm, P 〈 0.05）, RAD slightly also increased compared with the postoperative （36.1 ± 6.3 mm vs. 28.6 ± 5.5 mm, P 〈 0.05）, but did not recover to the preoperative level. TRA slightly increased compared with the postoperative, but the difference was not statistically significant （P 〉 0.05）. The PAP and left ventricular ejection fraction appeared no statistical difference compared with the postoperative （P 〉 0.05）, the remaining patients without serious complications. Conclusions： PBMV is a safe and effective procedure for MS combined with TR in patients of rheumatic heart disease. It can alleviate the symptoms and reduce the size of TR. It can also improve the quality-of-life and prognosis. Its recent and mid-term efficacy is certain. While its long-term efficacy remains to be observed.

Five-year Follow-up after Percutaneous Mechanical Mitral Commissurotomy

Objectives To assess five-year results after successful percutaneous mechanical mitral commissurotomy (PMMC). Methods Thirty-four selected patients with rheumatic mitral stenosis underwent PMMC successfully in Guangdong cardiovascular institute between February 2001 and August 2002. Serial echocardiograms were performed in all patients at baseline, discharge and annually thereafter. Results Five-year follow-up rate was 97.1%. Five-year survival rate was 100%. Before and after PMMC and at follow-up, mean mitral valve area by two-dimensional echocardiography was (0.87±0.15) cm2, (2.11±0.38) cm2 and (1.81±0.36) cm2, respectively (P<0.01). Five-year mitral restenosis rate was 6.1%. Conclusion PMMC can achieve excellent and sustained long-term results in selected patients with mitral echocardiographic score exceeding or being equal to 9.

Percutaneous balloon mitral valvuloplasty during pregnancy:A clinical analysis of 14 cases

Background Although acute rheumatic fever and rheumatic heart disease are now rare in affluent populations,they remain major health issues in developing countries such as China. Rheumatic mitral stenosis is the most common valvular disease during pregnancy. Some patients can receive percutaneous balloon mitral valvuloplastyduring pregnancy and obtain good outcomes. Methods A retrospective study of 14 women undergoing percutaneous balloon mitral valvuloplasty with rheumatic mitral valve stenosis during pregnancy in our hospital from Jan 2014 to Oct 2019 was conducted. The maternal and fetal outcomes were analyzed. Results Percutaneous balloon mitral valvuloplasty was successful in all patients with significant improvement in their mitral valve area(pre-operation:0.83±0.21 cm^2 and post-operation:1.64±0.27 cm^2,P<0.05). Pulmonary artery systolic pressure(pre-operation:69.62±28.27 mmHg and post-operation:37.23±12.65 mmHg,P<0.05)was significantly decreased. All 14 patients had an uneventful course afterthe operation. The total number of newborns was 14,none of whom required intensive care monitoring,and no malformations were found. Conclusions Percutaneous balloon mitral valvuloplasty performed during pregnancy with necessary precautions is feasible and effectivefor the mother and mightbe safe forthe fetus. There is marked symptomatic relief,along with good maternal and fetal outcomes.