Postoperative Low Cardiac Output State Research Articles

Del Nido cardioplegia in adult cardiac surgery: analysis of myocardial protection and post-operative high-sensitivity Troponin T.

del Nido cardioplegia has been adopted for use in adult cardiac surgery, despite a lack of robust randomised evidence supporting equivalence or superiority to conventional hyperkalaemic blood cardioplegia. We investigated the clinical surrogates of myocardial protection, and performed an extensive analysis of post-operative high-sensitivity Troponin T (hs-TnT) values in a general adult cardiac surgery population receiving del Nido, in comparison to a historical hyperkalaemic blood cohort. 171 consecutive patients of a single surgeon from between November 2018 and June 2020 received del Nido, and were compared to a historical cohort of 326 patients between January 2016 and November 2018 who received hyperkalaemic blood cardioplegia. Clinical markers of myocardial protection were compared, as were hs-TnT values at 6, 12, 24, and 72-h post-operatively. Equivalence between groups was determined using the two one-sided tests procedure. There was no difference between the groups in the incidence of post-operative low cardiac output state, inotropic support, or myocardial infarction. Del Nido patients had less defibrillation requirement, and more spontaneous resumption of normal sinus rhythm. High-sensitivity Troponin T values were similar at all time-points including in a coronary artery bypass graft subgroup, and in those patients with elevated pre-operative hs-TnT. In a broad cohort of adult cardiac surgery patients, including those undergoing coronary artery bypass surgery and those with recent myocardial infarction, del Nido provides equivalent myocardial protection and clinical outcomes when compared to hyperkalemic blood cardioplegia. Post-operative high-sensitivity Troponin T values were also equivalent between the groups.

The effects of thyroid hormones levels on prognosis after pediatric heart surgery

In this study, we aimed to evaluate the effects of thyroid hormone levels on the prognosis of patients who underwent congenital heart surgery under cardiopulmonary bypass. A total of 40 children who underwent congenital heart surgery were enrolled to this prospective study. The patients were divided into two groups according to the presence or absence of postoperative low cardiac output state. Plasma free thyroxine, free triiodothyronine and thyroid stimulating hormone levels were measured preoperatively and at 24 and 48 hours postoperatively. Postoperative low cardiac output state was observed in five patients (12.5 %). Preoperative free thyroxine levels were significantly higher in the low cardiac output state group (p=0.021). Postoperative free triiodothyronine and free thyroxine levels were significantly lower, and lactate levels, inotropic index were significantly higher in the low cardiac output state group. Duration of mechanical ventilation, intensive care unit stay, operation and cardiopulmonary bypass were significantly higher in the low cardiac output state group. Four patients (10 %) died in the early postoperative period, and all of them were in the low cardiac output state group. Our findings showed that the occurrence of low cardiac output state after congenital heart surgery was associated with the high levels of preoperative free thyroxine and the reduction in percentage of free triiodothyronine and free thyroxine levels at the 24th and 48th hours postoperatively.

Preoperative aldosterone receptor blockade and outcomes of cardiac surgery in patients with chronic kidney disease .

Recent clinical evidence demonstrates that chronic low-dose mineralocorticoid receptor antagonists (MRA), when added to optimal treatment, result in reductions in cardiovascular mortality. However, continuation of MRAs before cardiac surgery in patients with CKD has never been evaluated and its potential benefit or harm in this specific clinical setting is largely unknown. This is an observational study that included adult CKD patients undergoing cardiac surgery. Patients were divided into two groups according to preoperative use of spironolactone (SPL). The studied outcomes were postoperative acute kidney injury (AKI) requiring dialysis, mortality, and major morbidities (cardiovascular, neurologic, and infectious). Data on 698 patients with preoperative CKD stage III and IV were analyzed: 99 received SPL preoperatively and 599 did not. At baseline, patients on SPL had higher EuroScore and had more complicated surgery. No significant differences in the incidence of postoperative AKI, myocardial infarction (MI), cardiovascular accident (CVA), sepsis, and mortality were detected between groups in both univariate and multivariate analyses. However, incidence of postoperative low cardiac output state (p<0.008) was significantly higher in the SPL group. Propensity score matching analyses yielded similar results. Although SPL is usually administered to significantly sicker patients, its use is not associated with increased major postoperative complications. However, the modulating effect of SPL in this clinical study remains to be elucidated in a prospective randomized trial. .

Indications, timing and techniques of radical pericardiectomy via modified left anterolateral thoracotomy (ukc's modification) and total pericardiectomy via median sternotomy (holman and willett) without cardiopulmonary bypass

Background: Patients with constrictive pericarditis can be treated by pericardiectomy by either left anterolateral thoracotomy or median sternotomy. The terms “radical,” “total,” “extensive,” “complete,” “subtotal,” “adequate,” “near-total,” and partial pericardiectomy have been used often without much clarity. We describe our experience with a radical pericardiectomy technique via modified left anterolateral thoracotomy and compare the same to total pericardiectomy via median sternotomy. Methods: In this study, 67 (54.9%) patients underwent radical pericardiectomy via modified left anterolateral thoracotomy (Group I), and 55 (45.1%) patients underwent total pericardiectomy via median sternotomy (Group II). Results: The operative mortalities were 2.9% and 7.2% for the radical and total pericardiectomy groups, respectively. The time taken for normalization to Class I/II in Groups I and II was 30 ± 11 and 36 ± 14 days, respectively (P = 0.009). Surgical techniques did not affect the outcome of atrial fibrillation (P = 0. 77). Reoperation was not required for any patient. The radical pericardiectomy was also associated with less postoperative low cardiac output state as compared to patients undergoing total pericardiectomy (P < 0.001). There was no difference in mean duration of hospitalization; however, the radical pericardiectomy group achieved the New York Heart Association I and II Status quicker than the total pericardiectomy group (P = 0. 009). Conclusions: We conclude that using several technical modifications of pericardial excision, it is possible to achieve radical pericardiectomy via modified left anterolateral thoracotomy, particularly removing the constricting pericardium over the anterolateral, diaphragmatic surfaces of left ventricle and the anterior and diaphragmatic surfaces of the right ventricle until the right atrioventricular groove without using cardiopulmonary bypass in the great majority of patients undergoing pericardiectomy for chronic constrictive pericarditis. Although the surgical approach for pericardiectomy is based on surgeon's preference, left anterolateral thoracotomy is the preferred and noncontroversial approach in the setting of purulent pericarditis and effusive constrictive pericarditis to prevent sternal infection. We recommend median sternotomy approach with or without cardiopulmonary bypass, in the setting of calcific pericardial patches, pericardial masses, reoperations, and calcific pericardial “cocoon” and for those with predominant right-sided and annular involvement.

Remote ischemic preconditioning is a safe adjuvant technique to myocardial protection but adds no clinical benefit after on-pump coronary artery bypass grafting.

To evaluate the impact of remote ischemic preconditioning (RIPC) on clinical outcome, biological markers of myocardial injury, and its safety in patients undergoing on-pump coronary artery bypass grafting (CABG). This study was conducted at Ch. Pervaiz Elahi Institute of Cardiology (CPEIC) in Multan. The study took place from March 2012 to June 2013. Patients were randomly placed into two groups. Group A (N = 32) did not undergo RIPC; Group B (N = 35) received RIPC after induction of anesthesia. Similar standard general anesthesia, cardiopulmonary technique, myocardial protection strategies, and surgical techniques were used in both groups except the protocol for RIPC. Following postoperative outcome, i.e. cardiac defibrillation after removal of aortic cross clamp during the period of rewarming, demand for intra-aortic balloon pump (IABP), demand for antiarrhythmic before leaving the operation room, postoperative creatine kinase-myocardial band (CK-MB) level (at 1h, 12h, 24h, and 48h after surgery), postoperative serum creatinine level on first postoperative day, postoperative ejection fraction (EF) on third postoperative day, in-hospital mortality, and one-year mortality were noted, prospectively. Safety of protocol of RIPC was estimated by limb ischemia monitored by pulse oximetry during and after procedure of RIPC and postoperative neurapraxia by nerve examination of right upper limb. Post aortic cross clamp release cardiac defibrillation, demand for IABP, demand for high inotropes, and use of antiarrhythmic in the operation room were statistically insignificant in the non-RIPC and RIPC group with P values of .54, .78, .16, and .16, respectively. Mean postoperative CK-MB level (IU/L) showed the following results: At 1h (Group A 20.94 + 1.66, Group B 20.57 + 1.54, P = .35), at 12h (Group A 27.13 + 1.85, Group B 28.05 + 3.04, P = .135), at 24h (Group A 27.63 + 1.7, Group B 27.85 + 2.2, P = .63), and at 48h (Group A 22.95 + 2.76, Group B 23.27 + 3.6, P = .69). First postoperative day serum creatinine (Group A 1.29 + 0.395, Group B 1.33 + 0.57, P = .77) and postoperative ejection fraction percentage on the third postoperative day (Group A 50.78 + 8.72, Group B 50.57 + 8.38, P = .92) showed no statistical difference between two groups. Postoperative low cardiac output state, in-hospital mortality, and one-year mortality also were statistically insignificant between the groups with P values of .93, .29, and .33, respectively. None of the patients in either group showed evidence of limb ischemia and neurapraxia of the right upper limb. RIPC is a safe technique, but it does not have additional clinical benefit after on-pump CABG surgery in the presence of a standard myocardial protective strategy.

Neonatal and Paediatric Extracorporeal Membrane Oxygenation (ECMO) in a Single Asian Tertiary Centre

Extracorporeal membrane oxygenation (ECMO) is a cardiopulmonary bypass technique (CPB) which provides life-saving support in patients with refractory cardiorespiratory failure until cardiopulmonary recovery or organ replacement. This is a single centre retrospective study reporting the largest series of paediatric patients in Singapore who received ECMO support over an 11-year period from January 2002 to December 2012. The objective is to describe the characteristics of the patients and to report the survival to hospital discharge, complications during ECMO and other long-term complications. Forty-eight patients received ECMO during the study period. ECMO was initiated for myocarditis in majority of the paediatric patients whereas postoperative low cardiac output state was the most common indication in the neonatal population. The overall survival rate to hospital discharge was 45.8%. Survival was highest in the neonates with respiratory failure (75%). Haematological and cardiac complications were most common during ECMO. Age group, gender, duration of ECMO, need for renal replacement therapy, acute neurological complications were not associated with mortality. Those needing inotropic support during ECMO had poorer survival while those with hypertension requiring vasodilator treatment had a higher survival rate. The survival rates for ECMO patients more than doubled from the initial 6 years of 23% to 54% in the last 5 years of the study period. Long-term complications encountered included neurological, respiratory and cardiac problems. ECMO is a life-saving modality for neonatal and paediatric patients with cardiopulmonary failure from diverse causes. Patients with persistent need for inotropes during ECMO had poorer outcome. Centre experience had an impact on ECMO outcome.

Stroke After Coronary Bypass Surgery Is Mainly Related to Diffuse Atherosclerotic Disease

This study aims to investigate the risk factors for postoperative stroke and analysis of outcome after coronary bypass surgery with cardiopulmonary bypass. Between 1999 and 2008, 3248 consecutive patients who underwent isolated coronary surgery with cardiopulmonary bypass were prospectively enrolled in the study. Demographic and perioperative data were analyzed. Postoperative stroke was defined as severe adverse neurological events including permanent deficits or cerebral lesions with radiological demonstration of cerebral infarction within the first postoperative month. In total, 32 patients (0.9%) were determined with stroke. Univariate risk factors for postoperative stroke were determined as preoperative unstable angina (P = .006), Canadian Class of Angina (CCA) ≥ 3 (P = .001), preoperative creatinin level >1.2 mg/dL (P = .001), left main coronary artery disease (P = .04), chronic obstructive lung disease (P = .04), peripheral arterial disease (P < .001), New York Heart Association (NYHA) Class ≥ 3 (P = .004), preoperative renal insufficiency (P = .001), age > 65 years (P = .04), preoperative hypothyroidism (P = .02), postoperative low cardiac output state (P < .001), severe coronary artery disease requiring distal anastomosis ≥ 4 (P = .05), non-elective operation (P = .02), and body mass index ≥ 25 (P = .02). Multivariate analysis revealed peripheral arterial disease (odds ratio [OR], 5.2; 95% confidence interval [CI], 1.9-14.0; P = .001), severe coronary artery disease (OR, 3.1; 95% CI, 1.1-8.5; P = .02), and postoperative low cardiac output state (OR, 5.1; 95% CI, 1.4-18.2; P = .01) as the independent risk factors. Stroke after coronary bypass surgery with cardiopulmonary bypass is mainly related to diffuse atherosclerotic disease.

Extra-corporeal life support following cardiac surgery in children: analysis of risk factors and survival in a single institution

Application of extra-corporeal life support (ECLS) following pediatric cardiac surgery varies between different institutions based on manpower availability and philosophy towards ECLS utilization. We examined a large single institution experience with postoperative ECLS in children aiming to identify outcome predictors. Hospital records of all children who required postoperative ECLS at our institution were reviewed. Patients' demographics, cardiac anatomy, surgical and ECLS support details were entered into a multivariable regression analysis to determine factors associated with survival. Between 1990 and 2007, 180 consecutive children, median age 109 days (range: 1 day-16.9 years), required postoperative ECLS. Sixty-nine children (38%) had undergone palliative treatment for single ventricle pathology. ECLS support was required for failure to separate from cardiopulmonary bypass (n=83) or for postoperative low cardiac output state (n=97). Forty-eight patients (27%) received rescue extra-corporeal membrane oxygenation (ECMO) support during active chest compression for refractory cardiac arrest. Under ECLS support, 37 patients required surgical revision and 20 received orthotopic heart transplantation. One hundred and nine patients (61%) survived >24h following ECLS discontinuation and 68 (38%) were discharged alive. Hospital survivors required shorter ECLS support duration compared to non-survivors (median 3 vs 5 days, respectively, p=0.05) however survival occurred after up to 16 days of ECLS support. ECLS indication (OR: 0.85 for failure to separate from bypass vs postoperative low cardiac output 95% CI (0.47-1.56), p=0.62) and rescue ECMO (OR: 0.63 for rescue ECMO vs not 95%CI (0.32-1.24), p=0.18) were not associated with risk of mortality. In a multivariable logistic regression model, neurological complications (p=0.0007), prolonged ECLS duration (p=0.003), repeat ECLS requirement (p=0.02), renal dysfunction (p=0.04) and not performing heart transplantation (p=0.04) were significant factors for hospital death. ECLS plays a valuable role in children with low cardiac output state following cardiac surgery. More than one third of those patients, including young neonates, older children, patients with single ventricle, or those requiring rescue ECMO can be salvaged. Although prognosis worsens with prolonged ECLS duration, survival can be noted up to 16 days of support. Heart transplantation is often an important ECLS exit strategy and should be considered early in selected children. Patients' survival could improve if renal and neurological complications are avoided.

Severe ischemic early liver injury after cardiac surgery

Background. The epidemiology, pathogenesis and prognosis of severe ischemic early liver injury (SIELI) after cardiac surgery are poorly understood. Accordingly, we studied patients whose alanine transaminase (ALT) concentration acutely increased above 500 IU/l in the immediate postoperative period and compared these patients to two control groups matched for preoperative and immediate postoperative characteristics. Methods. We used a prospective database of 1,800 consecutive cardiac surgical cases to identify the study groups. Group I was made up of 20 patients with ALT levels above 500 IU/L in the acute postoperative stage (SIELI). Preoperative liver tests were normal in all these patients. Group II was obtained by identifying 20 control cases whose age, type of surgery, NYHA classification, and Parsonnet score matched Group I (preoperative controls). Group III was obtained by identifying 20 patients who developed postoperative acute renal failure and shock (ARF/shock; postoperative controls) but no enzyme evidence of hepatic injury. Results. Acute renal failure, a low cardiac index (CI) state, and mortality were more common in SIELI and ARF/Shock patients compared with preoperative controls (all p values less than 0.01). Peak postoperative pulmonary artery occlusion (PAOP) and central venous (CVP) pressures were also higher in SIELI and ARF/Shock patients than controls (all p values less than 0.02). A higher dose of norepinephrine and milrinone were required to maintain blood pressure and cardiac output in SIELI and ARF/shock patients than preoperative controls (all p values less than 0.005). SIELI patients, however, differed from ARF/Shock patients in that they had a higher preoperative NYHA class and a greater incidence of hypertension and diabetes. Stepwise linear regression analysis identified a postoperative low CI and the presence of diabetes as the only predictors of peak ALT value ( p less than 0.05). Multivariate logistic regression analysis identified female gender as being associated with a higher likelihood of SIELI (odds ratio: 6.13; 95% CI 1.08 to 34.82) Conclusions. SIELI after cardiac surgery carries a high mortality and is strongly associated with a low cardiac output and increased filling pressures, suggesting that liver ischemia induced by a combination of decreased perfusion and congestion is fundamental to its pathogenesis. A history of cardiac failure, diabetes, hypertension, and female gender may represent risk factors for its development and severity in the setting of a postoperative low cardiac output state.

Use of Enoximone in Weaning from Cardiopulmonary Bypass following Mitral Valve Surgery

Mitral valve surgery is often complicated by a postoperative low cardiac output state. In addition, some patients may have pre-existing pulmonary hypertension. Conventional inotropes, such as dopamine and dobutamine, tend to increase pulmonary vascular resistance. However, enoximone has both inotropic and vasodilatory properties. Ten patients, who had undergone mitral valve surgery and in whom weaning from cardiopulmonary bypass was unsuccessful without inotropic support, were treated with enoximone, 1 mg/kg loading dose plus 10 micrograms/kg/min continuous infusion, to assist in weaning from bypass. A significant and sustained increase in cardiac index was achieved without an increase in heart rate. At the same time, mean arterial pressure, systemic vascular and pulmonary vascular resistances were significantly decreased.

Evaluation of Conventional Circulatory Assist Devices: Intraaortic Balloon Pumping, Venoarterial Bypass, and Extracorporeal Membrane Oxygenation

This study was undertaken to reveal the limitations and problems with the conventional mechanical circulatory assist devices by analyzing the results in 70 cases; intraaortic balloon pumping (IABP group, n = 42), venoarterial bypass pumping (VAB group, n = 18), and extracorporeal membrane oxygenation (ECMO group, n = 10). The IABP could significantly prevent the development of postoperative low cardiac output state, and the best survival rate (62 percent) was obtained in the coronary arterial disease group. In the VAB group, eight (44 percent) cases were weaned, and four (22 percent) cases survived. These conventional assist devices could, though with limitations, certainly support the circulation and/or provide a period for it to recover, otherwise bridging the patients to new methods. The early decision not only for initiation of mechanical assist devices but also for moving to more definite procedures will improve the results with such devices.

Does Choice of Anesthetic Agent Significantly Affect Outcome after Coronary Artery Surgery?

A prospective study of 1094 consecutive adult patients undergoing coronary revascularization was undertaken to determine the effect of anesthetic technique on outcome. Patients received one of five primary techniques: high-dose fentanyl (greater than 50 micrograms/kg), moderate-dose fentanyl (less than 50 micrograms/kg), sufentanil (3-8 micrograms/kg), diazepam (0.4-1 mg/kg) with ketamine (3-6 mg/kg) or halothane (0.5-2.5% inspired concentration after thiopental induction). Supplemental inhalation anesthesia (enflurane, halothane, or isoflurane) was used in 60% of cases where the primary technique was intravenous based. Patients in the above anesthetic groupings had similar perioperative demographic and risk classifications. The overall incidence of postoperative myocardial infarction, postoperative low cardiac output state, and in-hospital death were 4.1, 5.6, and 3.1%, respectively. There were no significant differences in the incidence of these occurrences or in the incidence of serious pulmonary, renal, or neurologic morbidity or length of ICU stay among primary anesthetic techniques nor among supplemental inhalation agent groups. Multivariate discriminant analysis of this data suggests that a multitude of factors are significantly more important than anesthetic technique as determinants of outcome after coronary artery surgery.

Coenzyme Q 10: The Prophylactic Effect on Low Cardiac Output Following Cardiac Valve Replacement

A randomized, prospective study of the effectiveness of preoperative administration of coenzyme Q 10 on the prophylaxis of postoperative low cardiac output state was performed in 50 patients with acquired valvular diseases necessitating valve replacement. There were 25 patients in the treatment group and 25 in the control group. Patients in the treatment group received 30 to 60 mg of coenzyme Q 10 orally for six days before operation. Preoperative clinical variables, operative procedures, total cardiopulmonary bypass time, and aortic cross-clamping time were similar for the two groups. Postoperatively, mild to severe low cardiac output state developed in 28 of 50 patients (56%) and necessitated the administration of considerable amounts of inotropic agent. The treatment group showed a significantly lower incidence of low cardiac output state during the recovery period than the control group ( p < 0.05). These results suggest that preoperative administration of coenzyme Q 10 will increase the tolerance of human hearts to ischemia during aortic cross-clamping.

Predisposing factors of renal dysfunction following total correction of tetralogy of Fallot in the adult

A retrospective study of 21 adult patients with tetralogy of Fallot (TOF) was undertaken to determine the predisposing risk factors of renal dysfunction following total correction of the disease. Five of the 21 patients exhibited moderate-to-severe postoperative azotemia and an additional five exhibited mild azotemia. Significant risk factors for postoperative renal dysfunction found in routine preoperative examinations were as follows: arterial oxygen saturation of less than 90%, cardiothoracic ratio (CTR) of greater than 50%, mean electrical axis of the QRS complexes of greater than +120 degrees, S wave in Lead V6 of greater than 7 mm, R/S voltage ratio in Lead V6 of less than 2, and negative T wave in Lead V6. In addition, preoperative cardiac catheterization data showed that the patients exhibiting postoperative azotemia had more severe pulmonary stenosis, a smaller pulmonary-to-systemic flow ratio (Qp/Qs), and a larger left ventricular cavity than nonazotemic patients. The incidence of postoperative low cardiac output state (LOS) was significantly higher in the azotemic patients. These findings suggest that a combination of the severe form of TOF and a large left ventricle increase susceptibility to LOS and postoperative renal dysfunction. The cause and the clinical significance of the large left ventricular cavity in adults with TOF are discussed.