Myocardial Protection Techniques Research Articles

Investigation of the effects of cilostazol on the myocardial ischemia-reperfusion injury of rats.

<b><i>Background</i></b>. Myocardial ischemia, occurring as a consequence of imbalance between oxygen supply and demand, causes a rapid metabolic and structural<br /> impairment within the tissue. After a period of ischemia, sudden onset of reperfusion causes a transition to aerobic metabolism within living cells. Afterwards, emerging substrates initiate a chain of reactions leading to tissue injury. This situation is called “ischemia reperfusion injury”. Despite all technical advancements in anesthesia, myocardial protection and cardiac surgical techniques, we still face the clinical reflections of ischemia reperfusion (IR) injury.<br /> <b><i>Materials and methods</i></b>. The protective effect of cilostasole on IR injury in an animal model of experimental myocardial ischemia and reperfusion was investigated. In this regional myocardial ischemia model, male Wistar-Albino rats were used as subjects and they were allocated into three groups; ischemia (n=8), sham (n=8), and cilostazole (n=8). LAD was occluded for 45 minutes, and then reperfused for three hours. Rats received Cilostazole 20 mg/kg/d by gastric gavage once daily. During IR hemodynamic parameters were recorded. Serum analysis for CK-MB and Troponin T were analysed at 180th minute of ischemia. Ischemic zone was measured by dying with Evans Blue and infarct area was measured by dying with triphenyltetrazolium chloride.<br /> <b><i>Results.</i></b> Before the onset of LAD occlusion, as well as at 25th, 60th and 120th minutes of occlusion, all groups were similar in terms of blood pressure and pulse rate.<br /> The total area, affected area and necrotic area were calculated by using formulas; affected area ratio= affected area/total area X 100, necrotic area ratio = necrotic area/total affected area X 100, necrotic area and affected area ratio = necrotic area /affected area X 100.  Affected area and total area ratio was significantly higher in IR group, compared with cilostazole group (t=8.965; p<0.001). Similarly, necrotic area and total area ratio was higher in IR group, compared with cilostazole group (t=8.965; p<0.001). The necrotic area and affected area ratios were similar in IR and cilostazole groups (t=0.245; p=0.810). CK-MB level differences were not statistically significant between two groups (Z=0.382; p=0.721).<br /> Troponin levels were similar between IR and cilostazole groups and the difference was not statistically significant (Z=0.630; p=0.574). Pathological specimens of the heart were scanned for myocytolysis, PMNL and hemorrhage.  The difference between mean value of MDA enzyme levels were statistically significant (p<0.001) between all groups.  MDA enzyme levels, from higher to lower was IR, cilostazole and Sham group.  SOD levels (F=5.910; p=0.009) were significantly lower in Sham group when compared with IR group (p=0.008). The differences between Sham and cilostazole groups and IR and cilostazole gropus were not statistically significant (p=0.008). According to planimetric values and enzyme levels, cilostazole was found to be effective in reducing the ischemic zone, without effecting the necrotic zone in cardiac ischemia reperfusion damage. Therefore cilostazole has protective effects agains ischemia reperfusion damage.<br /> <br /> <b>Conclusion</b>. This study explored how cilostazol affects myocardial ischemia-reperfusion injury in rats, finding that cilostazol administration during reperfusion may protect against such injury. Through various analyses, we observed positive outcomes associated with cilostazol treatment, suggesting its potential in reducing myocardial damage. Further research is needed to understand the underlying mechanisms and optimize therapeutic strategies, but our findings highlight cilostazol's promise in improving clinical outcomes in cardiac interventions.

N-terminal pro-B type natriuretic peptide as a predictor for myocardial preservation in cases of isolated severe Aortic stenosis

Background Myocardial hypertrophy is a common pathologic finding in the natural history of severe aortic stenosis. A hypertrophied myocardium predisposes the patient to decreased tolerance to ischemia and increased reperfusion injury, myocardial protection is of utmost importance in patients undergoing aortic valve replacement (AVR) for severe aortic valve stenosis. Myocardial protection techniques during cardiac arrest have been extensively investigated in the clinical setting of coronary revascularization. However, fewer studies have been carried out on patients affected by left ventricular (LV) hypertrophy, where the choice of type, and temperature of cardioplegia remains controversial. Aim The study investigates preoperative N-terminal pro-B type natriuretic peptide (NT pro-BNP), its relation to Troponin I levels, and whether it can predict a preferred cardioplegic solution by comparing the short-term outcomes of the two commonly used blood and Histidine-Tryptophan-Ketoglutarate (HTK) cardioplegic solutions in patients undergoing aortic valve replacement for severe aortic stenosis. Patients and methods A total of 72 patients will be randomly allocated into two groups; group (A=36) received HTK solution, and group (B=36) received blood cardioplegia. All anesthesia protocols are unified among all patients. All surgical procedures were conducted on a cardioplegic arrested heart via standard median sternotomy, utilizing full Cardiopulmonary bypass (CPB) via aorto-atrial cannulation and LV venting through a left atrial catheter under moderate hypothermia (28–32°C) by topical cooling. Results There was no statistically significant difference found between group A and group B regarding post-operative ejection fraction (EF) and newly developed postoperative Regional wall motion abnormalities (RWMA). There was no statistically significant difference found between group A and group B regarding the percentage of patients with atrial fibrillation, ventilation hours, and exploration while there was a statistically significant increase in troponin, I level in group B than group A. There was a statistically significant negative correlation between NT pro-BNP preoperative and aortic valve area (AVA) and also with ejection fraction preoperative while there was a statistically significant positive correlation found between NT pro-BNP and troponin I preoperative and postoperative. Conclusion HTK solution and Blood cardioplegia both offer sufficient protection for the myocardium. NT pro-BNP serves as a sensitive indicator for predicting the results and effectiveness of different cardioplegia types

BNP, TnI and Lactic Acid variations in Warm Blood Cardioplegia vs Cold Crystalloid Cardioplegia in Coronary Artery Bypass Grafting (CABG)

Introduction: Myocardial protection is one of the key points during cardiac surgery. Inadequate myocardial protection in cross-clamping period is an issue of concern in cardiac surgery. Cardioplegic solutions improve the tolerance of ischemia and reperfusion by preserving myocardial energy reserves, preventing osmotic, electrolyte imbalances and acidosis. Warm blood cardioplegia (WBC) has had a profound impact, especially in coronary artery bypass surgery and there have been many studies that compared it with Cold crystalloid cardioplegia (CCC). A good myocardial protection will be reflected especially on patients outcome, on postoperative ICU strategy, morbidity and mortality as well. Brain Natriuretic Peptide (BNP), Troponin I (TnI) and Lactic Acid LA) are very significant biomarkers that reflects an adequate myocardial and organ perfusion/protection. The purpose of this study is to determine if warm blood cardioplegia offers any advantages in comparison with CCC in Coronary Artery Bypass Grafting (CABG) based primary on variations of BNP, TnI and Lactic Acid. Patients and method: 60 patients with coronary artery disease (CAD) that will have Coronary Artery Bypass Surgery (CABG), were retrospectively randomized in two groups of 30 patients with different techniques of myocardial protection: group A had CCC, and group B had warm blood cardioplegia (WBC), according to Calafiore [1] protocols). Intraoperative and postoperative variables were used to assess primary outcomes. Results: This study found benefits of warm blood cardioplegia in clinical outcome after CABG Keywords :Myocardial protection, Cardiac surgery, Cardiopulmonary Bypass, Calafiore, Cardioplegia, Coronary Artery Bypass Grafting (CABG), Brain Natriuretic Peptide (BNP), Troponin I (TnI) and Lactic Acid LA) DOI: 10.7176/ALST/95-02 Publication date: November 30 th 2022

Single centre experience of double valve replacement using mechanical valves

Introduction: Cardiac valvular disease in India is most commonly caused by Rheumatic aetiology, many of which end up getting operated for the same. There is still existing controversy about the selection of ideal valves that can be used for replacement. Objective: Objective of this study was to retrospectively analyse the variable which can be easily assessed in the patients undergoing DVR (Double Valve replacement) using mechanical valves for its outcomes. Methods: All the patients who underwent DVR + Tricuspid valve repair/annuloplasty between October 2017 to January 2019, were identified and retrospectively their data was analysed. Results: 72 patients who underwent the procedure. Most common aetiology was Rheumatic. 69.4% were in NYHA (New York Heart Association) class II, 33.33% had chronic atrial fibrillation. 45.6% had associated tricuspid valve disease, and no chordae was preserved in 27.7%. Overall mortality was 5.5% Conclusion: The study revealed a favourable survival outcome after DVR surgery. The operative mortality in patients undergoing DVR depends on intra operative factors like total surgical time, bypass time and aortic cross clamped time and has improved remarkably over time, with the improvisation of extracorporeal circulation methods, myocardial protection techniques and postoperative management.

Myocardial Protection with Glucose-Insulin-Potassium Infusion during Cardiopulmonary Bypass for Coronary Revascularization

Background: Sodi-Pallares and colleagues first time introduced use of glucose-insulin and potassium (GIK) solution for myocardial protection. They used this solution in patients with acute myocardial infarction and concluded that GIK solution limited electrocardiographic changes in these patients. Objective: To investigate the effectiveness of the GIK solution regarding myocardial protection evaluated by postoperative creatine kinase MB (CKMB) and cardiac troponin I levels. Method: In this prospective, randomized clinical trial, sixty-four patients were assigned into two groups: GIK group, in which glucose-insulin and potassium infusion were given during surgery, and non-GIK group in which only saline infusion was given during the procedure. Results: All CK-MB values were lower in the GIK group than the Non-GIK group in the postoperative period (6, 12 and 24 hours’ samples) with statistically significant results. Troponin values were lower in the GIK group versus the Non-GIK group after 6 and 12 hours with statistical significance (P < 0.001 and 0.022 respectively). Conclusion: The addition of GIK infusion throughout the operation to standard myocardial protective techniques in patients undergoing on-pump coronary artery bypass graft (CABG) surgery attenuates myocardial ischemic injury.

Mitral Valve Replacement Surgery in Redo Patients with Mix Blood Cardioplegia (MBC) Protection

Aim of Study : Redo patient undergoing valve surgery are always a challenge for both cardiac surgeon and anesthesiologists. Mix blood cardioplegia has had a profound impact on cardiac surgery. but there have been few studies on its use in mitral valve replacement, especially in redo patient. The purpose of this study was to determine whether mix blood cardioplegia offers any advantages in redo patient undergoing mitral valve replacement. Patients and Methods : 20 patient, who have had a previous mitral valve surgery and were scheduled for mitral valve replacement with or without tricuspid repair, were randomized retrospectively to one of two groups of 10 with different technique of myocardial protection: group A (10 patients) had cold crystalloid cardioplegia, and group B(10 patients) had mix blood cardioplegia, a technique modified on our clinic condition (made by mixing 400-500ml oxygenated blood from oxygenator and 10ml KCL 7.5%) . Systemic hypothermia was 28°C in Group A and between 32°C and 33°C in Group B. The results were primarily assessed on the basis of clinical outcome, such as hematocrit level intra and post CPB, maximum dose of inotropic support, spontaneous rhythm recovery after aortic cross clamping, length of intensive care unit stay and secondly on postoperative blood loss and blood requirements. Results : There were no preoperative or operative differences between the groups with regard to age, sex, diagnosis, rhythm, New York Heart Association functional class, left ventricular ejection fraction, estimated pulmonary artery systolic pressure, operation, or duration of the operation, CPB, or aortic cross clamping and the time when the patients underwent the first operation. There was one death in group A (10% mortality). The changes in hematocrit level differs significantly between the two groups on the post CPB period (p=0,02) There appeared to be a trend towards better spontaneous recovery of sinus rhythm after removal of the aortic cross clamp in group B compared with group A, the difference did reach statistical significance. (p=0.002). Patients on group A required more inotropic support than Group B (p=0.005). There were differences even on blood requirements postoperatively, more dominant these requirement were in group A (p=0.02). Discussion : Mix Blood Cardioplegia had beneficial effects in clinical outcome in redo patients undergoing mitral valve replacement surgery. This may be due to its better preservation of high-energy phosphates and endogenous amino acids, less anerobic metabolic activity on reperfusion, reduced release of cardiac troponin T, and improved post-ischemic functional recovery. Keywords: Miocardial protection, cardiopulmonary bypass CPB, Mix Blood Cardioplegia (MBC) DOI: 10.7176/ALST/82-04 Publication date: October 31 st 2020

Del Nido Cardioplegia Versus Cold Blood Cardioplegia in Adult Cardiac Surgery: Protocol for a Randomized Controlled Trial.

BackgroundThe use of cardioplegia solutions as a myocardial protection technique is essential during cardiac surgery with cardiopulmonary bypass. The del Nido cardioplegia solution (DNS) has been widely used as a myocardial preservation technique for pediatric patients undergoing cardiac surgery with cardiopulmonary bypass. Its unique pharmacological features have created growing interest for adult cardiac surgery, especially for elderly patients or those with ventricular dysfunction who are more prone to ischemia-reperfusion injury. Ever since its implementation, several retrospective studies have been published to validate the efficacy, safety, and efficiency of DNS in adult patients undergoing coronary revascularization, valve replacement, or combined procedures. Recently, a meta-analysis based on nine retrospective studies was published claiming the noninferiority of DNS compared to other conventional cardioplegia solutions. Few prospective randomized studies have been conducted whose primary outcome was the assessment of DNS clinical efficacy compared to other solutions commonly used in adult patients.ObjectiveThe aim of this randomized clinical trial is to assess the benefits of DNS compared to Cardi-Braun blood cardioplegia solution in clinical and biochemical terms regarding myocardial protection during adult cardiac surgery.MethodsThis is the protocol of a controlled, randomized, single-center clinical trial carried out at the Puerta de Hierro Majadahonda University Hospital in Spain. A total of 474 participants over the age of 18 years undergoing elective cardiac surgery with cardiopulmonary bypass will be assigned to groups by simple randomization to receive either DNS or Cardi-Braun blood cardioplegia solution. The primary outcome will be the differences between groups in myocardial protection in biochemical terms (ie, perioperative troponin levels) and clinical terms (ie, presence of the composite variable acute cardiovascular event). The clinical trial will be carried out under conditions of respect for the fundamental rights of the person and the ethical principles that affect biomedical research with human beings, as well as in accordance with international recommendations contained in the Declaration of Helsinki and its subsequent revisions.ResultsThe inclusion process started in 2018. Data cleaning and analyses are expected to take place in the fall of 2020 and the results are expected in January 2021.ConclusionsThis study is particularly relevant as it will be one of the first to analyze the clinical effects of del Nido cardioplegia on the basis of direct myocardial protection parameters. In light of published studies, carrying out prospective studies based on primary clinical objectives with a larger sample, high-risk patients, and longer cardiopulmonary bypass times continues to be necessary. We believe that our study addresses an important gap in the knowledge of del Nido cardioplegia in adult patient cardiac surgery and will be able to clarify the possible benefits of this method in a large population of patients undergoing these procedures.Trial RegistrationEuropean Union Drug Regulating Authorities Clinical Trials Database (EudraCT) 2017-005144-14; https://www.clinicaltrialsregister.eu/ctr-search/search?query=2017-005144-14+; ClinicalTrials.gov NCT04094168; https://clinicaltrials.gov/ct2/show/NCT04094168International Registered Report Identifier (IRRID)DERR1-10.2196/17826

Myocardial protection: a forgotten modality.

The goals of a cardiac surgical procedure are both technical excellence and complete protection of cardiac function. Cardioplegia is used almost universally to protect the heart and provide a quiet bloodless field for surgical accuracy. Yet, despite the importance of myocardial protection in cardiac surgery, manuscripts or dedicated sessions at major meetings on this subject have become relatively rare, as though contemporary techniques now make them unnecessary. Nevertheless, septal dysfunction and haemodynamic support (inotropes, intra-aortic balloon pump, assist devices) are common in postoperative patients, indicating that myocardial damage following cardiac surgery is still prevalent with current cardioplegic techniques and solutions. This article first describes why cardiac enzymes and septal function are the ideal markers for determining the adequacy of myocardial protection. It also describes the underappreciated consequences of postoperative cardiac enzyme release or septal dysfunction (which currently occurs in 40-80% of patients) from inadequate protection, and how they directly correlate with early and especially late mortality. Finally, it reviews the various myocardial protection techniques available to provide a detailed understanding of the cardioplegic methods that can be utilized to protect the heart. This will allow surgeons to critically assess their current method of protection and, if needed, make necessary changes to provide their patients with optimal protection.

Predictors of clinical outcome after mitral valve replacement

Background: To identify and study predictors of morbidity, mortality, and survival after mitral valve replacement. Methods: We have examined 186 patients undergoing isolated mitral valve surgery between January 2013 to January 2015, with respect to preoperative clinical features, echocardiographic findings, hemodynamics and surgical approaches. Coronary angiography was done as a routine in all patients above 40 yrs of age & coronary artery bypass grafting with mitral valve replacement was done in 7 patients. The operative mortality was 5.37%. Postoperatively patients were followed up at 3 months interval for first 1 year & at 6 months interval thereafter. Results: Multivariate statistical analysis demonstrated that patients age > 60 years, patients with symptoms NYHA Class–IV, ventricular arrhythmias, associated disease (Coronary artery disease, Infective endocarditis), end diastolic diameter measuring ≥60 ± 10mm, left atrial Dimension ≥ 65 mm, chordal preservation (Partial / Total) independently influenced the morbidity and Mortality. Conclusion: Strategies to diminish operative mortality should include careful assessment of the risks factors in elderly patients, early operative intervention before deterioration that necessitates urgent surgery, and use of improved techniques of myocardial protection in high-risk patients.

Cold crystalloid versus warm blood cardioplegia in patients undergoing aortic valve replacement.

Myocardial protection techniques during cardiac arrest have been extensively investigated in the clinical setting of coronary revascularization. Fewer studies have been carried out of patients affected by left ventricular hypertrophy, where the choice of type and temperature of cardioplegia remain controversial. We have retrospectively investigated myocardial injury and short-term outcome in patients undergoing aortic valve replacement plus or minus coronary artery bypass grafting with using cold crystalloid cardioplegia (CCC) or warm blood cardioplegia (WBC). From January 2015 to October 2016, 191 consecutive patients underwent aortic valve replacement plus or minus coronary artery bypass grafting in normothermic cardiopulmonary bypass. Cardiac arrest was obtained with use of intermittent antegrade CCC group (n=32) or WBC group (n=159), according with the choice of the surgeon. As compared with WBC group, in CCC group creatine-kinase-MB (CK-MB), cardiac troponin I (cTnI), aspartate aminotransferase (AST) release, and their peak levels, were lower during each time points of evaluation, with the greater statistically significant difference at time 0 (P<0.05, for all comparisons). A time 0, CK-MB/CK ratio >10% was 5.9% in CCC group versus 7.8% in WBC group (P<0.0001). At time 0 CK-MB/CK ratio >10% in patients undergoing isolated aortic valve replacement was 6.0% in CCC group versus 8.0% in WBC group (P<0.01). No any difference was found in perioperative myocardial infarction (0% versus 3.8%), postoperative (PO) major complications (15.6% versus 16.4%), in-hospital mortality (3.1% versus 1.3%). In aortic valve surgery a significant decrease of myocardial enzymes release is observed in favor of CCC, but this difference does not translate into different clinical outcome. However, this study suggests that in presence of cardiac surgical conditions associated with significant left ventricular hypertrophy, i.e., the aortic valve disease, a better myocardial protection can be achieved with the use of a cold rather than a warm cardioplegia. Therefore, CCC can be still safely used.

P5809Hypoxic-hyperoxic preconditioning: a novel technique for myocardial protection against ischemia-reperfusion injury in coronary surgery

P5809Hypoxic-hyperoxic preconditioning: a novel technique for myocardial protection against ischemia-reperfusion injury in coronary surgery

Factors influencing the outcome of double valve replacement surgery

Background: Data on the influence of surgical variables in mortality and morbidity of patients undergoing double valve replacement (DVR) surgery are scarce. Objective of this study was to identify preoperative, intra operative and post operative factors associated with mortality and morbidity of patients undergoing DVR surgery.Methods: Between 2010 and 2016, patients who underwent double (Mitral and Aortic) valve replacement at our institution were analyzed. These patients were studied retrospectively for preoperative data and postoperative outcome including causes of deaths and the data was analyzed statistically.Results: There were 150 patients, 107 were male (71.3%) and 43 were female (28.6%) Present study revealed a high mortality rate among female patient undergoing DVR surgery than males, which is statically significant at p&lt;0.05. Pre operatively 100 patients (66.6%) were class IV NYHA symptoms. This study finds a significant correlation between preoperative NYHA and hospital mortality with higher mortality rate in NYHA class IV patients with p-value &lt;0.00001 which is significant at p&lt;0.05. Long-term survival was also seen to be significantly dependent on the preoperative LVEF. Among intra operative parameter average total surgical time was 197.70 minutes (3.29 hours); average total cardio pulmonary bypass time was 82.67 minutes (1.37 hours) and average cross clamp time was 67.28 minutes (1.12 hours). Outcome groups (in-hospital death vs. hospital discharge) had a significant statistical difference in relation to variables, respectively: aortic cross clamp time (in minutes) of 77.66 and 67.40 (p=0.001); CPB 95.66 and 84.63 (p=0.006); and total surgical time 208.75 and 186.04 (p=0.002). Among the post operative complications, immediate complications occurring within 7 days of surgery were; low cardiac output syndrome in 9.3% (n=14), bleeding leading to exploration was 8% (n=12), refractory arrhythmias in 3% (n=5), sepsis in 4% (n=6) and acute renal failure in 2% (n=3). Inter mediate post-operative complications (7 to 30 days of surgery) were wound infection in 26 patients (17.3%). There was no incidence of stuck valve or pulmonary thrombo embolism Overall mortality was 8% (12 patients) all within 30 days of operation. There was no statistical difference between the outcome and the types of prostheses used, either biological or metallic (p=0.219).Conclusions: The study results have demonstrated a favourable survival outcome after DVR surgery. An advance age, female sex, a higher NYHA class, poor left ventricular function are associated with poor outcome. The operative mortality in patients undergoing DVR also depends on intra operative factors like total surgical time, CPB time and aortic cross clamped time and has improved remarkably over time, with the improvisation of extracorporeal circulation methods, myocardial protection techniques and postoperative management.

Prevalence of co-morbidities among adult patients presented for open heart surgery and the implication on convalescence period

Background: Improvements in perioperative medical care, anesthetic management, surgical and myocardial protection techniques made cardiac surgery feasible in the high risk surgical patients. The aim of the study was to determine the prevalence of comorbidities in adult patients undergoing open heart surgery and to evaluate their implications on recovery profile.Methods: This randomized retrospective observational study of 100 adult patients presented for heart surgery for different pathologies took place at Queen Alia heart Institute in the period of time between February 2013 and June 2014. Patients' data was collected in forms, tabulated and retrospectively analyzed. Patients' demographics, co-morbidities and type of surgery were recorded. Risk stratification models (ASA-American Society of Anesthesiology and EUROSCORE 2- European system for cardiac operative risk evaluation) were used. Time of extubation, ICU discharge and hospital discharge was recorded with each patient.Results: Age of patients ranged from 18 to 77 years (mean±SD: 58±12). 83% of patients were male and 17% were female. 80 patients were presented for CABG and 20 patients for heart valve(s) surgery. BMI (body mass index, mean±SD) was 28.9±4.6 kg/m². The prevalence of smoking was 56% (6 times higher among males (64%), in comparison to females (12%). Hypertension was prevalent in 72% of patients; diabetes was present in 53%, respiratory disease in 30%, previous myocardial infarction in 23%, 37% of patients had left ventricular impairment, renal impairment in 6%, renal failure in 2% and previous stroke in 2%. EUROSCORE values ranged between 0.5 to 5.3 % (mean 1.4%). ASA grades ranged from 2 to 4 (85% of patients were grade 3). 5% of surgeries were emergent. Average operative time was 248±47 minutes (mean±SD). 30% of patients needed inotropic support and 6% needed intra-aortic balloon. Mean time in the intensive care was 43.2±28.8 hours (mean±SD).Conclusions: There is a high prevalence of co-morbidities in patients presented for cardiac surgery. Most common associated diseases were hypertension, obesity, smoking, previous myocardial infarction and diabetes; which are all well known risk factors of ischemic heart disease. Preoperative risk scoring is of paramount importance.

Results of Mitral Valve Surgery with Pulmonary Arterial Hypertension: Analysis of a Retrospective Study

Introduction: Rheumatic heart diseases are redoubtable complication of acute articular rheumatic. Without treatment, pulmonary hypertension and right heart failure may occur. This pulmonary hypertension was admitted as predictor of worse outcome after surgery. The aim of our study is to value the results after mitral surgery in patients with moderate and severe pulmonary hypertension. Methods: This is an observational descriptive retrospective study between January 2006 and December 2012; a total of 201 patients were operated for mitral or mitro-tricuspid disease with pulmonary arterial hypertension in “Djeghri Mokhtar” hospital. These patients are divided into two groups according to preoperative pulmonary hypertension (PAH) degree: (Group A: 102 patients in moderate PAH, 40 ≤ sPAP<60 mmHg; Group B: 99 patients in severe PAH, Spap ≥ 60 mmHg). In our study, sPAP was measured with doppler echocardiography. Preoperative, operative and postoperative data collection included age, sex, functional class, type of surgery and cardiopulmonary bypass. Pulmonary arterial systolic pressure, left atrial diameter, left ventricular end-diastolic diameter, and left ventricular ejection fraction were recorded and compared. Results: The follow up is in mean of 61.73 months (from 30 to 108 months). The functional class was improved in majority of patients. There is a significant decrease in mean sPAP during follow up:(48.72 ± 5.85 versus 29.12 ± 8.29 mmHg in group A;77.90 ± 15.62 versus 28.87 ± 10.61 mmHg in group B). Global hospital mortality is 0.49% (0% in group A, 0.98% in group B). Late mortality is 2.48%( 3.92% in group A; 1.01% in group B). Survival at 05 years is 96.5%. Conclusion: Pulmonary arterial systolic pressure decreased near normal value in most patients after surgery. Severe pulmonary hypertension must not be an absolute contraindication for mitral surgery, the outcome has been improved by developing cardiopulmonary bypass, myocardial protection and anesthetic technique.

Remote vs. local ischaemic preconditioning in the rat heart: infarct limitation, suppression of ischaemic arrhythmia and the role of reactive oxygen species

The unmet clinical need for myocardial salvage during ischaemia-reperfusion injury requires the development of new techniques for myocardial protection. In this study the protective effect of different local ischaemic preconditioning (LIPC) and remote ischaemic preconditioning (RIPC) protocols was compared in the rat model of myocardial ischaemia-reperfusion, using infarct size and ischaemic tachyarrhythmias as end-points. In addition, the hypothesis that there is involvement of reactive oxygen species (ROS) in the protective signalling by RIPC was tested, again in comparison with LIPC. The animals were subjected to 30-min coronary occlusion and 90-min reperfusion. RIPC protocol included either transient infrarenal aortic occlusion (for 5, 15 and 30 min followed by 15-min reperfusion) or 15-min mesenteric artery occlusion with 15-min reperfusion. Ventricular tachyarrhythmias during test ischaemia were quantified according to Lambeth Conventions. It was found that the infarct-limiting effect of RIPC critically depends on the duration of a single episode of remote ischaemia, which fails to protect the heart from infarction when it is too short or, instead, too prolonged. It was also shown that RIPC is ineffective in reducing the incidence and severity of ischaemia-induced ventricular tachyarrhythmias. According to our data, the infarct-limiting effect of LIPC could be partially eliminated by the administration of ROS scavenger N-2-mercaptopropionylglycine (90 mg/kg), whereas the same effect of RIPC seems to be independent of ROS signalling.

Cardiovascular Surgery in the Elderly

The elderly population is the fastest growing demographic in Western countries. As the population ages, the incidence of age-related comorbidities such as diabetes mellitus, chronic obstructive pulmonary disease, peripheral vascular disease, renal disease, cerebrovascular disease, and cardiovascular disease increases. With cardiovascular disease occurring in approximately one-quarter of the population over the age of 75 years and more than half of all cardiac procedures performed on this age group, the number of potential elderly surgical candidates is increasing. However, data suggest that old age is associated with increased morbidity and mortality following cardiac surgery. Over the past 2 decades, improvements in myocardial protection, extracorporeal circulation, anesthesia, and surgical techniques have significantly reduced the morbidity and mortality associated with cardiac surgery. Although most prospective studies exclude elderly patients, data from large retrospective studies and subgroup analyses suggest that cardiac surgery is a viable option for many elderly patients with cardiovascular disease, with good outcomes observed in reasonable-risk candidates; moreover, there are a growing number of available less-invasive options for them when surgical risk becomes prohibitive. In this article, we discuss the current state of cardiovascular surgery in the elderly as well as emerging technologies on the horizon.

Clinical Results of Different Myocardial Protection Techniques in Aortic Stenosis.

BackgroundHypertrophied myocardium is especially vulnerable to ischemic injury. This study aimed to compare the early and late clinical outcomes of three different methods of myocardial protection in patients with aortic stenosis.MethodsThis retrospective study included 225 consecutive patients (mean age, 65±10 years; 123 males) with severe aortic stenosis who underwent aortic valve replacement. Patients were excluded if they had coronary artery disease, an ejection fraction <50%, more than mild aortic regurgitation, or endocarditis. The patients were divided into three groups: group A, which was treated with antegrade and retrograde cold blood cardioplegia; group B, which was treated with antegrade crystalloid cardioplegia using histidine-tryptophan-ketoglutarate (HTK) solution; and group C, treated with retrograde cold blood cardioplegia.ResultsGroup A contained 70 patients (31.1%), group B contained 74 patients (32.9%), and group C contained 81 patients (36%). The three groups showed significant differences with regard to the proportion of patients with a New York Heart Association functional classification ≥III (p=0.035), N-terminal pro-brain natriuretic peptide levels (p=0.042), ejection fraction (p=0.035), left ventricular dimensions (p<0.001), left ventricular mass index (p<0.001), and right ventricular systolic pressure (p<0.001). Differences in cardiopulmonary bypass time (p=0.532) and aortic cross-clamp time (p=0.48) among the three groups were not statistically significant. During postoperative recovery, no significant differences were found regarding the use of inotropes (p=0.328), mechanical support (n=0), arrhythmias (atrial fibrillation, p=0.347; non-sustained ventricular tachycardia, p=0.1), and ventilator support time (p=0.162). No operative mortality occurred. Similarly, no significant differences were found in long-term outcomes.ConclusionAlthough the three groups showed some significant differences with regard to patient characteristics, both antegrade crystalloid cardioplegia with HTK solution and retrograde cold blood cardioplegia led to early and late clinical results similar to those achieved with combined antegrade and retrograde cold blood cardioplegia.

Carbon dioxide insufflation and neurocognitive outcome of open heart surgery.

Neurocognitive dysfunction continues to be the bane of open heart surgery despite vast improvements in surgical, anesthetic, and postoperative management. This observational cohort study was carried out to evaluate the efficacy of intraoperative CO2 insufflation by the field flooding technique in reducing postoperative neurocognitive dysfunction. Three hundred randomly selected patients undergoing open heart surgery were observed: 150 (group A) were exposed to CO2 insufflation, and the other 150 (group B) were not exposed to CO2. Anesthetic, cardiopulmonary bypass, and myocardial protection techniques were standardized and similar in both groups. Neurocognitive function tests were performed preoperatively, 1 week postoperatively, and after 1 month. The analysis revealed that neurocognitive dysfunction occurred in 8 of 150 patients in group A (incidence p1 = 0.053) and 27 of 150 in group B (incidence p2 = 0.18). The relative risk of neurocognitive dysfunction was 0.30 (p = 0.001, 95% confidence interval 0.14-0.63), implying that CO2 insufflation is protective against neurocognitive dysfunction. The risk difference was 0.13 (p2-p1); this implies that 13% of patients can be prevented from developing neurocognitive dysfunction if exposed to CO2. This study confirms the known advantage of the relatively underutilized practice of CO2 insufflation. We recommend that CO2 insufflation be performed in all open heart surgery cases to bring down the incidence of neurocognitive dysfunction. This technique is simple to use without any major paraphernalia or additional cost.

Use of del Nido Cardioplegia for Adult Cardiac Surgery at the Cleveland Clinic: Perfusion Implications

Cardiac arrest by cardioplegia provides a reproducible and safe method to induce and maintain electromechanical cardiac quiescence. Techniques of intraoperative myocardial protection are constantly evolving. For the past three decades, modified Buckberg cardioplegia solution has been used for adult cardiac surgery at the Cleveland Clinic. This formulation serves as the crystalloid component, which is delivered 4:1 with oxygenated patient’s blood to crystalloid. Meanwhile, our use of the del Nido cardioplegia solution in adult patients, heretofore primarily used in pediatric cardiac surgical centers, has been increasing over the past several years. Single-dose, cold blood del Nido cardioplegia can be delivered antegrade if the duration of the operation will be limited and if there is no significant coronary artery disease or aortic insufficiency that would limit the distribution of cardioplegia. The addition of del Nido cardioplegia to our cardioplegia armamentarium allows us to customize our myocardial protection strategies for different surgical needs. This article aims to provide information on technical aspects of del Nido cardioplegia in adult cardiac surgery and its use at the Cleveland Clinic in the adult surgical population.

Review: Outcomes of Revascularization Strategies for Coronary Artery Disease

The optimal revascularization strategy for patients with coronary artery disease is influenced by the continuous improvement in medical therapy and the improved designs of the new generation of coronary stents allowing them to be increasingly applied in patients with complex coronary anatomy, including those with left main stem disease. On the other hand, surgical results are also improved as a result of the increased experience over years and the improvement of myocardial protection techniques. This will make the comparison of percutaneous coronary interventions and coronary artery bypass surgery a moving target. In this paper, we reviewed the recent randomized controlled trials and important registries emphasizing the benefits and the results of each therapy in different patient subsets. A heart team of both cardiologists and cardiac surgeons is of paramount importance in choosing the optimal revascularization strategy.