Evaluation the critical care period results after isolated mitral valve replacement or simultaneous mitral and aortic valve surgery in patients with pulmonary hypertension

Nội dung text: Evaluation the critical care period results after isolated mitral valve replacement or simultaneous mitral and aortic valve surgery in patients with pulmonary hypertension

1. Journal of military pharmaco-medicine n o2-2018 EVALUATION THE CRITICAL CARE PERIOD RESULTS AFTER ISOLATED MITRAL VALVE REPLACEMENT OR SIMULTANEOUS MITRAL AND AORTIC VALVE SURGERY IN PATIENTS WITH PULMONARY HYPERTENSION Kieu Van Khuong*; Pham Thi Hong Thi**; Nguyen Quoc Kinh*** SUMMARY Objectives: To assess the early outcome after elective isolated or concomitant mitral valve replacement (MVR) in patients with pulmonary hypertension (PH). Subjects and methods: The study included patients with baseline systolic pulmonary artery pressure (PAPs) of at least 35 mmHg measured by echo who underwent elective MVR and/or aortic valve replacement (AVR). The systemic and pulmonary hemodynamic changes, arterial and mixed venous blood gas parameters were reported at various time points before and after operation. Preoperative and postoperative transthoracic echocardiography was performed. Results: Sixty seven patients (15 males and 52 females), arithmetic mean age was 45.51 ± 10.74 years (min - max: 20 - 68) were included in the study. The operative mortality rate was 4.5%. The receiver operating characteristic curves identified PAPs as a good predictor of operative mortality. Postoperatively, there was a significant reduction in left atrial diameter (LAd). The arithmetic mean PAPs and pulmonary artery occlusion pressure (PAOP) decreased significantly after cardiopulmonary bypass (CPB) and persisted throughout the study period. Central venous pressure (CVP) decreased after CPB time and remained so to PAC removing time point, postoperatively. A decrease in SvO 2 was significant after operation. Conclusion: Proper perioperative care and anesthetic techniques resulted in the improvement of LAd, PAPs, PAOP, with acceptable operative mortality in patients with PH who was performed elective isolated MVR or simultaneous mitral and AVR. * Keywords: Pulmonary hypertension; Aortic valve replacement; Mitral valve replacement. INTRODUCTION in stenosis and/or regurgitation heart valve diseases. Where surgery is indicated, All around the world, rheumatic heart MVR is usually necessary [1]. The disease remains a major health problem, development of pulmonary arterial although its prevalence in the developed hypertension (PAH) has been considered countries is much reduced. Involvement a risk factor for poor outcomes in patients of the mitral valve and aortic valve results undergoing MVR and/or AVR [2]. However, * 103 Military Hospital ** Vietnam National Heart Institute *** Vietduc Hospital Corresponding author: Kieu Van Khuong (icudoctor103@gmail.com) Date received: 10/12/2017 Date accepted: 22/01/2018 154
2. Journal of military pharmaco-medicine n o2-2018 there is no consensus on the outcome of prosthesis. The hemodynamic and arterial patients with PAH after MVR in the blood gas parameters were reported at literature; some studies have shown that time points: T0: baseline or pre-induction; severe PAH is associated with poorer T1: post-intubation; T2: immediate post- outcome and higher mortality rate [3], CPB; T3: at ICU; T4: 6 hour post-ICU; T5: whereas others do not agree that severe 24 hour post-ICU and Toff: before PAC PAH implies a higher risk during corrective removing and the hemodynamics had been surgery [4, 5, 6, 7]. stabilized postoperatively. Hemodynamic parameters that were recorded included This study was designed to: Assess mean arterial pressure (MAP), PAPs, the early clinical, hemodynamic, and PAOP, and central venous pressure echocardiographic changes after elective (CVP). All data were expressed as mean isolated MVR or concomitant MVR and ± standard deviation, min - max or AVR in patients with PH. number and percent as appropriate. SUBJECTS AND METHODS The preoperative and postoperative echocardiographic parameters, and the 1. Subjects. hemodynamic and arterial blood gas Between April, 2017 and November, parameters obtained at various time 2017, 67 consecutive adult patients with a intervals were compared with the baseline baseline PAPs of at least 35 mmHg (as values. The receiver operating characteristic measured by preinduction transthoracic (ROC) curves were used to estimate the echocardiography) who had performed relationship between sensitivity (proportion mitral and/or simultaneous AVR at Heart of true positive cases) and 1-specificity Center of Hue Center Hospital. Patients (proportion of false-positive cases) of with coronary artery disease or idiopathic PAPs in the prediction of operative PAP were excluded from the study. mortality. A p-value of 0.05 or less was 2. Methods. considered significant. All preoperative assessments were RESULTS carried out by two-dimensional transthoracic echocardiography. A pulmonary artery Table 1: Patient’s characteristics. catheter (PAC) was placed in the pulmonary artery to measure PAPs and PAOP. Variables Result Min - max General anesthesia was induced with Age (year) 45.5 ± 10.7 20 - 68 fentanyl, 3 - 5 µg/kg. All patients were Gender [m/f, (%)] 15/52 operated on through a arithmetic mean (22.4/77.6) sternotomy on CPB with moderate general Body surface area (m 2) 1.44 ± 0.11 hypothermia (28 - 30°C). We used two kinds of mechanical prosthesis: ATS valve Body mass index 19.8 ± 2.4 15.4 - 25.2 2 and St Jude medical bileaflet mechanical (kg/m ) 155
3. Journal of military pharmaco-medicine n o2-2018 Weight (kg) 48.0 ± 6.5 33 - 67 (ACC: Aortic cross-clamp time; CPB: Cardiopulmonary bypass time; IABP: Height (cm) 155.9 ± 7.0 142 - 170 Intra-aortic balloon pump; ICU: Intensive NYHA II (n, %) 21 (31.3) care unit. LAA: Left atrial appendage) NYHA III (n, %) 44 (65.7) The arithmetic mean CPB time was 114.18 ± 57.71 mins (range: 54 - 466) NYHA IV (n, %) 2 (3) and the arithmetic mean aortic cross- Atrial fibrillation (n, %) 31 (46.3) clamp time was 79.76 ± 36.78 mins Cardiothoracic ratio 40 (59.7) (range: 31 - 185). Tricuspid repair was > 50% (n, %) performed in 15 patients (22.39%). Table 3: Comparison of preoperative The study group was mainly female and postoperative echocardiographic (77.6%) at arithmetic mean age of 45.51 ± variables. 10.74 years. The patients were classified as follows: 21 patients (31.3%) in NYHA II Variables T0 T3 Toff class and 44 patients (65.7%) in NYHA III class and 2 cases in NYHA class IV. 51.03 ± 42.13 ± 43.67 ± Lad (mm) b b b 8.19 2.30 2.88 Table 2: Intraoperative and postoperative clinical outcome variables. LVEDD 48.28 ± 45.92 ± 45.45 ± (mm) 8.31 b 5.59 b 5.19 b Min - Variables Result LVESD 34.66 ± 32.61 ± 31.87 ± Max (mm) 7.15 b 5.40 b 5.31 a CPB time (min), 114.2 ± 54 - 466 53.49 ± 53.28 ± 55.21 ± EF (%) arithmetic mean 57.7 8.02 7.38 8.22 ACC time (min), 79.8 ± 31 - 185 arithmetic mean 36.8 (a: Significant difference < 0.0001; Tricuspid repair [n (%)] 15 b: Significant difference < 0.05. Abbreviation: (22.4%) EF: Ejection fraction; Lad: Left atrium LAA exclusion [n (%)] 18 (26.9) diameter; LVEDD: Left ventricular end- Thromboembolic 11 (16.4) diastolic diameter; LVESD: Left ventricular removing [n (%)] end-systolic diameter; CTR: Cardiothoracic Time of ventilator (h) 20.9 ± ratio) 31.7 There was a significant difference Mechanical assist by 4 (6%) between LAd, LVEDD, LVESD at points IABP [n (%)] time of postoperation and when to remove Operative mortality 3 (4.5%) PAC in comparision with baseline time [n (%)] results but no significant difference in EF. 156
4. Journal of military pharmaco-medicine n o2-2018 Table 4: Early hemodynamic parameter changes. Time points CI (L/min/m 2) CVP (mmHg) MAP (mmHg) PAPs (mmHg) PAOP (mmHg) T0 2.43 ± 0.77 a 7.55 ± 4.11 b 94.48 ± 12.41 a 49.15 ± 17.52 a 23.43 ± 9.84 a T1 1.66 ± 0.42 a 7.08 ± 3.21 67.66 ± 10.22 a 29.91 ± 11.08 a 16.48 ± 7.54 a T2 2.58 ± 0.61 a 8.49 ± 2.80 74.54 ± 14.22 a 32.45 ± 10.31 a 11.40 ± 4.16 a T3 3.02 ± 0.80 a 6.21 ± 2.99 b 93.01 ± 13.34 33.13 ± 11.94 a 9.63 ± 5.91 a T4 2.65 ± 0.55 a 6.10 ± 2.79 b 74.00 ± 11.63 a 32.18 ± 11.89 a 9.91 ± 5.43 a Toff 3.00 ± 0.69 a 6.21 ± 3.20 b 79.16 ± 10.70 a 31.45 ±1 1.99 a 9.63 ± 5.06 a (a: Significant difference < 0.0001; b: Significant difference < 0.05. Abbreviation: CI: Cardiac output index; CVP: Central venous pressure; MAP: Mean arterial pressure; POAP: Pulmonary artery occlusion pressure; PAPs: Pulmonary systolic arterial pressure) There was a significant decrease in PAPs, PAOP after induction, CPB stop, and this change persisted throughout at removing PAC time point postoperatively. CVP and MAP decreased, but it kept in normal range. CI decreased after induction anesthesia (T1) and increased significantly at T2, T3, Toff time point. Table 5: Arterial and mixed venous blood gas parameter changes. Time points pH PaCO 2 (mmHg) PaO 2 (mmHg) SaO 2 (%) SvO 2 (%) T0 7.42 ± 0.03 38.24 ± 4.22 210.64 ± 96.08 99.19 ± 1.99 72.57 ± 9.34 a T1 7.48 ± 0.06 a 32.48 ± 5.54 a 319.56 ± 80.85 a 99.94 ± 0.37 b 72.37 ± 8.10 T2 7.45 ± 0.07 b 31.53 ± 6.40 a 301.00 ± 82.54 a 99.85 ± 0.76 74.53 ± 8.78 T3 7.40 ± 0.07 b 34.84 ± 8.35 b 175.43 ± 62.35 b 99.05 ± 1.20 69.19 ± 10.55 T4 7.39 ± 0.07 b 36.29 ± 5.88 b 163.98 ± 36.34 b 99.14 ± 0.66 63.34 ± 12.43 a Toff 7.45 ± 0.07 b 39.46 ± 6.19 104.50 ± 36.74 a 96.86 ± 2.67 a 59.24 ± 11.17 a (a: Significant difference < 0.0001, b: Significant difference < 0.05) There was a significant difference of blood gas parameters between baseline time point (T0 time point) with other time points, excepted PaCO 2 (Toff time point), PaO 2 (T2 time point), SaO 2 (T2, T3, T4 time point) and SvO 2 (T1, T2, T3 time point). 157
5. Journal of military pharmaco-medicine n o2-2018 PAPs 100 80 60 Sensitivity: 66.7 Specificity: 85.9 40 Criterion : >65 Sensitivity 20 0 0 40 80 100-Specificity Figure 1: The receiver operating characteristic curve of systolic pulmonary arterial hypertension as a predictor of operative mortality. DISCUSSION 36.8 mins) was similar to Xiaochun Song’s study (CPB: 119.9 ± 37.4 mins and ACC: There were 67 patients involved in the 82.5 ± 31.8 mins) [7]. Our result was study, the lowest age was 20, the highest higher than Vu Thuc Phuong’s study was 68, the mean was 45.51 ± 10.74 years. (CPB time of group D, using dobutamin: This finding is consistent with recent studies 95.2 ± 35.1 mins; CPB time of group E, in cardiac valve surgery in India and using epinephrine: 86.5 ± 24.1 mins. ACC Vietnam. The study by Nirmal Kumar et al time of group D: 73.5 ± 32.4 mins; ACC [7] in severe PH patients soon after MVR time of group E 67.2 ± 20.8 mins). It may had an arithmetic mean age of 32.1 years, be due to their patient groups were mainly lower than our result. This difference was replaced one valve surgery (> 60% in both due to the fact that study only included groups) and no preoperative heart failure. patients with mitral valve disease with severe PH (PAPs > 50 mmHg) and this A comparison of preoperative and feature was more common in acute postoperative (T3 time point), removing rheumatoid arthritis in India [10]. Age in PAC time point (Toff) echocardiographic our study was similar to result of Gökhan variables is presented in table 3. Postoperatively, there was a significant Lafçı [4] and two other local authors: Vu reduction in LAd, LVEDD, LVESD Quynh Nga (44.2 ± 11.5 years), Doan (p < 0.05). The increased left atrial (LA) Duc Hoang (46.69 ± 12.57 years) [1, 2]. pressure in mitral valve disease is passively The patients were mainly in NYHA III transmitted to the pulmonary vasculature with 46.3% rhythm dysfunction as atrial and can lead to an increase in pulmonary fibrillation (AF) and 59.7% of them vascular resistance (PVR). Some other increased cardiothoracic ratio over 50%. factors such as reactive pulmonary Some intraoperative and postoperative vasoconstriction and organic changes in results showed in table 2. The arithmetic pulmonary vasculature are also responsible mean CPB time (114.2 ± 57.7 mins) and for this increase in PVR [11]. Following the arithmetic mean ACC time (79.7 ± mitral valve surgery, LA loading can 158
6. Journal of military pharmaco-medicine n o2-2018 be adequately decompressed. This The present study showed that MVR decompression is very influential in the could be performed in patients with regression of PH [4]. LA enlargement is a rheumatic valvular disease and severe pathophysiological response to volume PH with an acceptable operative mortality overload resulting from valvular diseases of 10%. The study by Mubeen et al [12] which is known as LA remodeling, and showed that the operative mortality was has been shown previously to be associated 5.5% in patients with subsystemic PAP, with cardioembolic events. Following MVR, with a mean of 58.1 mmHg and 28.5% in the LA may undergo reverse remodeling patients with a suprasystemic PAP of characterized by LA volume reduction. LA 83.2 mmHg. The operative mortality rate size reduces with the return of normal in our study was 4.5% (table 2). The ROC sinus rhythm and a decrease in the curves (figure 1) identified PAPs as a gradient across the mitral valve. good predictor of operative mortality (area Our results showed a significant decrease under the ROC curve: 0.794; p < 0.05), in PAPs and PAOP after CPB (T2 time and the value greater than 65 mmHg has point), and this change persisted to time the highest specificity (85.9%) and point of PAC removing, postoperatively sensitivity (66.7%) for the risk of operative (table 4 ). These findings were in agreement mortality in those patients. Similarly, the with some other researchers who have recent study by Corciova et al identified reported hemodynamic changes in patients PAPs value greater than 65 mmHg to with rheumatic mitral valve disease at have the highest specificity and sensitivity different intervals after MVR, with an for the risk of perioperative death in mitral immediate reduction in PAPs. In the study regurgitation patients (area under the by Kumar [9], the mean PAPs, PAOP, and ROC curve: 0.782; p < 0.001). pulmonary vascular resistance decreased significantly soon after CPB in patients SvO 2 did not change at T1, T2 time with severe PH. The mean PAPs point (table 5) but it decreased significantly approached near-normal values (26 ± after operation even when hemodynamic 5 mmHg) 6 hours and 24 hours, in stable (at Toff time point). SvO 2 can be postoperatively. The study by Mubeen et used to assess the adequacy of tissue al [12] showed that the mean PAPs perfusion and oxygenation. When analyzing decreased by 38% from a mean in conjunction with other hemodynamic preoperative level of 59.8 to 37.1 mmHg parameters, following trends in the SvO 2 immediately following MVR. Although it does offer insight into cardiac performance continued to decrease over the next and tissue oxygen delivery. In the 24 hour, this further decrease was not postoperative cardiac surgical patient, a statistically significant. In a recent study fall in SvO 2 generally reflects decreased by Bayat et al, PAP in patients with severe oxygen delivery or increased oxygen PAH showed no significant reduction extraction by tissues and is suggestive of immediately after MVR, but it decreased a reduction in cardiac output. However, significantly below the range of severe other constantly changing factors that PAP over the first 24 hours after operation. affect oxygen supply and demand may 159
7. Journal of military pharmaco-medicine n o2-2018 also influence SvO 2 and must be taken 4. Lafci G, A.I Diken, H.S Gedik et al. into consideration. These include shivering, Alterations in pulmonary artery pressure temperature, anemia, alteration in FiO 2, following mitral valve replacement. Turk and the efficiency of alveolar gas exchange. Kardiyol Dern Ars. 2012, 40 (3), pp.235-241. A decresae in SvO 2 at T3, T4 time point 5. Svein Simonsen K.F. Anders Andersen (patients in ventilation support) (table 5) and Leif Efskind Hospital mortality after mitral can result from a decrease CO, low valve replacement. 1974. hemoglobin level or an increase in oxygen 6. Parvathy U.T, R. Rajan, A.G. Faybushevich. consumption. SvO 2 decreased at Toff Reversal of abnormal cardiac parameters may be relative with a decrease in FiO 2 following mitral valve replacement for severe (in room air), fever or anemia. It is very mitral stenosis in relation to pulmonary artery important to take care the patients in this pressure: A retrospective study of noninvasive stage because SvO 2 reduction under parameters - early and late pattern. Interv threshold leads to the danger of organ Med Appl Sci. 2016, 8 (2), pp.49-59. dysfunction that is reason why they come 7. Song X.C, Zhang X. Chen et al. An back to intensive care unit ward. excellent result of surgical treatment in patients with severe pulmonary arterial CONCLUSION hypertension following mitral valve disease. J Isolated MVR or concomitant MVR and Cardiothorac Surg. 2015, 10, p.70. AVR was safe and effective even in 8. Thunberg C.A, B.D Gaitan, A. Grewal patients with PH, with acceptable operative et al. Pulmonary hypertension in patients mortality and a significant improvement in undergoing cardiac surgery: pathophysiology, left atrial diameter, pulmonary hemodynamics perioperative management and outcomes. J. (PAPs, PAOP), but a decrease in mixed Cardiothorac Vasc Anesth. 2013, 27 (3), venous saturation early after operation. pp.551-572. The anesthetic technique and perioperative 8. Kumar N.P. Sevta S, Satyarthy et al. care can be useful in improving the Early results of mitral valve replacement in outcome in such patients. severe pulmonary artery hypertension - An institutional prospective study. World Journal REFERENCE of Cardiovascular Surgery. 2013, 3 (2), pp.63-69. 1. Ho ằng Đ.Đ. Nghiên c ứu vai trò c ủa ch ỉ 10. Padmavati S. Present status of rheumatic fever and rheumatic heart disease in India. số SvO 2 trong h ồi s ức huy ết độ ng ở b ệnh nhân ph ẫu thu ật tim có nguy c ơ cao. 2017. Indian Heart J. 1995, 47 (4), pp.395-398. 2. Nga V.Q. Nghiên c ứu m ột s ố thông s ố 11. Ott B. Valvular heart disease a companion huy ết độ ng và ch ức n ăng tim b ằng siêu âm to Braunwald's heart disease expert consult Doppler ở b ệnh nhân ph ẫu thu ật thay van hai third edition. 2009. lá Sorin Bicarbon. 2010. 12. Mohammad Mubeen, Amrendra K 3. Zakkar M, E. Amirak, K.M. Chan et al. Singh, Surendra K Agarwal, Jeewan Pillai, Rheumatic mitral valve disease: current surgical Shalini Kapoor, Ashok K Srivastava . Mitral status. Prog Cardiovasc Dis. 2009, 51 (6), valve replacement in severe pulmonary pp.478-481. arterial hypertension. 2008. 160