Cardiac Surgery in Patients with Dialysis-dependent End Stage Renal Failure: Single Centre Experience

BACKGROUND

Patients under dialysis have a high cardiovascular risk and they are at increased risk when submitted to cardiac surgery.

AIM OF THE STUDY

to evaluate morbidity, early and late mortality, and predictive factors of mortality in patients under dialysis who underwent cardiac surgery.

METHODS

A retrospective observational study was performed including all dialysis dependent patients who underwent cardiac surgery (coronary, valvular or combined procedures) in our institution between 2007 and 2014. A population of 95 consecutive patients was obtained (no exclusions). Perioperative variables and predictors of mortality were analysed and the endpoints were early and late mortality. Propensity score matching, with a control group of patients with creatinine clearance >90mL/min, was performed by logistic regression, with a 1:1 matching. Kaplan Meier curves were performed for late mortality.

RESULTS

Early mortality was 9.4% (EuroSCORE II 4.1%). In univariate analysis, mean time of cardiopulmonary bypass (CPB) (p=0.016) and EuroSCORE II (p=0.02) were related with early mortality. In a multivariate analysis model, combined procedures (OR 138.09; CI95% 1.82-10498.4; p=0.03) and CCS (Canadian Cardiovascular Society) 3-4 (OR 70.951; CI 95% 1.32-3810.11; p=0.037) were predictors of mortality. In multivariable analysis, CPB time >152 min was a predictor of early mortality (p=0.001). After propensity score matching, 30 day, one year and late mortality were higher in the dialysis group.

CONCLUSIONS

Early and late mortality were significantly higher in dialysis dependent patients. Predictive factors of mortality were CPB time and EuroSCORE II in univariable analysis, and CCS 3-4 and combined procedures in multivariable analysis.

Trauma: An Unusual Cause of Endocarditis

INTRODUCTION

Infective endocarditis (IE) remains a dangerous condition with considerable associated mortality. Usual risk factors for IE include the presence of a prosthetic heart valve, structural or congenital heart disease, intravenous drug use, and a recent history of invasive procedures.

METHODS

The authors describe the case report of a patient with IE having trauma as an unusual risk factor.

RESULTS

A 33-year old male patient was referred to our department due to infective endocarditis. The patient had a fever of unknown origin for 15 days before going to the emergency department. After admission it was identified by transthoracic echocardiography a 14mm posterior abscess of the aortic valve provoking major aortic regurgitation with moderate LV dysfunction. After careful evaluation of the clinical history it was found that the patient had a known bicuspid aortic valve with follow-up since the age of 14. All other usual risk factors for IE were excluded, including intravenous drug use and recent history of invasive procedures. The only relevant previous event was a traumatic haemathoma in his left jaw caused by a working accident with an iron beam in a construction site as the patient is a civil engineer. Vancomycin plus gentamicin were empirically started after blood cultures taken. The isolated infective agent was Staphylococcus lugdunensis methicillin sensitive and the antibiotherapy was de-escalated to flucloxacilin plus gentamicin. Due to cardiac dysfunction the patient was submitted to cardiac surgery on the fourth day of directed antibiotic therapy and a replacement of the aortic valve by a mechanical prosthetic valve and closure of the abscess with bovine pericardial patch was performed. The valve sent to microbiology evaluation showed the same infective provocative agent. The patient had a good clinical and laboratorial recovery completing the 42-day antibiotic scheme. After antibiotherapy period completion, echocardiography was repeated and the abscess found was larger then the previous one, presenting itself like an aortic pseudo aneurysm. The patient was resubmitted to surgery with re-closure of the initial abscess with autologous pericardial patch and replacement of the prosthetic mechanical valve for an undersized one. The patient was discharger clinically well, having a complete normal life at the moment.

CONCLUSION

This clinical case illustrates trauma as an unusual cause of endocarditis and emphasizes the importance of a detailed clinical history.

David Operation in the Bicuspid Aortic Valve Population

INTRODUCTION

Bicuspid aortic valve (BAV) is the single most common cardiac congenital mal-formation with a prevalence of 1-2%. It is frequently associated with aortic disease including annular ectasia. Increasing evidence suggests that valve-sparing root re-implantation surgery combined with primary aortic valve repair can be performed with good midterm results in patients with BAV.

METHODS

Our objective is to compare the short and long term results of David procedure in BAV patients with aortic root ectasia. Retrospective analysis of our institution's database retrieved 42 patients with aortic annular ectasia who underwent valve-sparing root re-implantation surgery with David technic from 2007 to 2015. This cohort included 11 patients with BAV and 31 with tricuspid aortic valve (TAV). Pre, intra and post-operative variables of these two groups were statistically analyzed using univariate analysis. Continuous variables are expressed as means+-standard deviation. Categorical variables are expressed as percentages. Univariate analysis was performed using students t-test for continuous variables and x2 for categorical variables. Long-term survival and freedom from re-intervention was analyzed using Kaplan-Meier curves.

RESULTS

Follow-up was achieved in 100% of cases with an average follow-up of 60 months. Mean age of the studied population was 50 years. Comorbidities and demographics were similar in the BAV and TAV groups with the exception of a younger operative age in the BAV group (p=0,028). Mean cardiopulmonary bypass time and mean ischemic time was 162' and 133' respectively. Combined procedures were performed in 3 (7,1%) of patients. The BAV group showed longer cardio- pulmonary bypass e aortic cross-clamp times (p=0,024; p=0,022) and a universal need for aortic plasty. Short-term results and complications were similar in the two groups with the exception of a higher need for pacemaker implantation in the BAV group (p<0,001). Post-operative results including in-hospital mortality, stroke, AMI, pre-discharge echocardiographic evaluation and long-term survival and freedom from re-intervention were similar between the two groups.

CONCLUSION

Our experience reinforces the idea that, however challenging, the aortic valve sparing re-implantation procedure in the setting of BAV, has acceptable short and long-term results, similar to those observed in TAV patients. The pitfalls of this setting are the universal need for aortic valve plasty and higher risk for AV block. A more significant cohort of patients; echocardiographic long-term evaluation and long-term comparison with the gold-standard technic (Bentall procedure) may further clarify the benefits of this approach in BAV patients.

Bilateral Internal Thoracic Artery Grafting in Patients with Diabetes Mellitus

INTRODUCTION

Bilateral internal thoracic artery (BITA) grafting in patients with diabetes mellitus is controversial due to a higher risk for sternal infection. The purpose of this study is to compare the rates of mediastinitis as well as mortality rates of BITA grafting to that of single internal thoracic artery (SITA) grafting and saphenous vein grafts in patients with diabetes.

METHODS

Between 2007 and 2015 all consecutive diabetic patients with multivessel disease who underwent primary coronary artery bypass graft surgery with BITA were compared with patients who underwent coronary artery bypass graft surgery with SITA and saphenous vein grafts (the control group). Patients submitted to single grafts were excluded from the analysis. Propensity score matching was used to account for differences between groups in preoperative characteristics. The frequency of peri-operative mediastinitis was compared between BITA and control group. Mortality rates between were compared between groups at 1-month post-surgery and 2-year post-surgery.

RESULTS

A total of 1005 patients were included in our sample in which 188 (19%) patients performed BITA grafting. BITA patients were younger (BITA group mean age 60.0 years vs control group 69.9 years; p<0.001), less often female (BITA group 11.7% vs control group 28.2%; p<0.001), and less often insulin treated (BITA group 9.6% vs control group 18.8%; p=0.002) compared to the control group. All other characteristics were not statistically different between groups, namely CCS, NYHA score, three vessel coronary artery disease, left main disease, previous myocardial infarction, hypertension, COPD and body mass index. After propensity score matching, 344 patients were included in the analysis, 138 in the BITA group and 206 in the control group. In this analysis both groups were not statistically different in every characteristic evaluated including age, sex and insulin-treated diabetic patients. The rate of peri-operative mediastinitis in matched groups was comparable (BITA group 2.3% vs control group 1.5; p=0.605). Mortality rates were comparable between groups at 1-month post-surgery (BITA group 1.4% vs control group 0.5%; p=0.346) and 2-year post- -surgery (BITA group 3% vs control group 2%; p=0.557).

CONCLUSION

The findings of this sample suggest that the short and mid-term outcomes of patients with diabetes and multivessel disease who undergo BITA grafting is similar to other grafting procedures. BITA grafting in diabetic patients seems to be safe in terms of sternal wound problems. Longer term follow-up is required to determine BITA grafting survival improvement.

Diagnostic Challenges in Chronic Constrictive Pericarditis

INTRODUCTION

Chronic constrictive pericarditis (CCP) is a disease that has multiple possible causes and is associated with variable clinical findings, depending on its severity. It develops insidiously, and in many cases, particularly in developed countries, no antecedent diagnosis can be found. These cases are termed idiopathic. Tuberculosis is the leading cause of constrictive pericarditis in developing nations but represents only a small minority in developed countries.

METHODS

Here the authors describe two different case reports where tuberculosis was the probable cause of CCP.

RESULTS

A 21-year-old man born in Cape Verde living in Europe for 4 years and a 24-year-old man born in Guiné Bissau were both admitted due to intense precordial pain and syncope after exertion. Interestingly both had fatigability, dyspnea, chest discomfort and palpitations on exertion, as well as progressive involuntary weight loss and decubitus cough. On physical examination they had tachycardia, jaundice, cachexia, elevated jugular venous pressure, hepatomegaly and ascites. Both electrocardiograms showed prominent P waves and chest X-ray showed bilateral pulmonary interstitial infiltrates and enlargement of the right cavities. Analytically, elevated bilirubin, leukopenia and thrombocytopenia was also found in both. Echocardiography revealed findings, in both cases, compatible with CCP including less common signs as annulus reversus and annulus paradoxus. Thoraco-abdomino-pelvic CT from both patients revealed chronic liver disease with congestion, pleural effusion, pericardial calcifications, ascites and massive mediastinal and abdominal adenopathies. Blood cultures and IGRA test were negative. However, given the presumptive diagnosis of tuberculosis (TB), anti-TB therapy was started. Despite the diagnosis of "end-stage" CCP with very high operative risk multidisciplinary team decided after informed consent, to perform total anterior pericardiectomy, that occurred without complications. Pericardial and mediastinal biopsies, pericardial/pleural fluid cultures/ immune-phenotyping were inconclusive. Anti- tuberculosis therapy was maintained. After surgery, the patients had a remarkable clinical improvement (NYHA I) that persisted in 6- month follow-up.

CONCLUSION

These two case reports illustrate that despite the markedly elevated operative risk of pericardiectomy in "end-stage" forms of disease after patients informed consent must be a considered option. The other point to consider is that, despite rare, tuberculosis still is a possible diagnosis to consider in CCP in Portugal.

Benign Presentation of a Potentially Fatal Disease

Anomalous origin of the left coronary artery from the pulmonary artery is a rare congenital cardiovascular defect that can range from being fatal early in life to presenting in adulthood asymptomatically. We report the case of a teenager whose diagnosis was incidental and underwent surgery, consisting in coronary artery button transfer, with excellent result.