Aortic Valve Replacement Surgery Research Articles

Unique carotid-vertebral occlusive disease in a patient admitted for cardiac surgery

A 62-year-old male patient was admitted to undergo aortic valve replacement surgery for severe aortic stenosis. As part of preoperative preparation, a computed tomography (CT) angiography showed o...

PCV59 Economic Burden Associated with the Management of Mycobacterium Quimaera Endocarditis from the Perspective of a Spanish Hospital

Mycobacterium Chimaera (M.Chimaera) is a highly resistant microorganism responsible for the development of severe infections in patients undergoing cardiothoracic surgeries with extracorporeal circulation. Infections become clinically apparent after a time lag of months to years and lead to significant mortality and morbidity. Recommended treatment includes a combination of multiple antimicrobial drugs and the removal of foreign material. The aim of this study was to determine the cost associated with the management of a M.Chimaera endocarditis from a Spanish hospital perspective. A cost analysis was developed based on previously published results on health resource use (HRU) of the management of a prosthetic infective endocarditis. Unit costs were applied to estimates of HRU comprising diagnostic tests, hospital length of stay and pharmacological treatment. Costs were obtained from different Spanish sources and expressed in €2020. Deterministic sensitivity analysis was performed to assess the robustness of the base case results. The mean cost of the management of a M. Chimaera infection was €93,470.68 (€84,123.61- €102,817.75). Inpatient length of stay (121 days) represented the major cost driver (€77,936.79; 83.4%) followed by the pharmacological treatment (€5,058.99; 5.4%) and the aortic valve replacement surgery (€4,59.49; 4.9%), respectively. M. Chimaera associated infections represent a relevant economic burden for the hospitals. Current prevention strategies such as heater-cooler units disinfection protocols, and equipment removal from the operating room have clinically demonstrated to be insufficient and costly. Innovative machines such us non-toxic glycol based HCUs should be taken into consideration due to its proven long-term bactericidal properties in order to avoid potential infections in patients undergoing chest surgeries.

AN EARLY EGYPTIAN EXPERIENCEIN OZAKI TECHNIQUE

Background: The advantage of Ozaki technique for aortic valve replacement surgery over the conventional approach is still debated. This study aimed to evaluate early outcomes after aortic valve replacement using the Ozaki technique Methods: We prospectively included 20 patients who had aortic valve replacement May 2018 to June 2020. Postoperative bleeding, mechanical ventilation, ICU stay and echocardiographic outcomes were observed. Results: The mean age was 39.9±14.8 (20-69) years.13 patient had aortic regurge while 7 had aortic stenosis. Aortic cross-clamp (76.2±8.5 (60-100) and cardiopulmonary bypass times (103.8±15.3 (80-125).One patient (5%) was converted to aortic valve replacement by mechanical valve due to significant aortic regurge. Neither significant gradient nor regurge was found on one month follow-up echography. Freedom from infective endocarditis was found in all patients. No significant difference was found in the ejection fraction pre and post-operative. Conclusion: This novel technique seems to have a promising and favorable outcome with no need for anticoagulation and lesser post-operative complication compared to ordinary aortic valve replacement. This technique is associated with low mortality and morbidity.

Does Blood Transfusion Have an Effect on Outcomes After Aortic Valve Replacement Surgery?

Long-term outcomes following surgical aortic valve replacement (AVR) are excellent. However, there is a significant early morbidity burden. Red cell transfusion is common in the perioperative period and deleterious effects of receiving a transfusion on early postoperative morbidity are well described in observational studies. This study aimed to assess the effect of transfusion on ischaemic or infective outcomes after aortic valve replacement. Data from 270 patients enrolled in the Manubrium-limited ministernotomy versus conventional sternotomy for aortic valve replacement (MAVRIC) randomised controlled trial was used to create two cohorts, patients that received red cell transfusions following AVR and those that did not. Propensity score matching was performed to limit the effect of confounding variables. Strict transfusion thresholds were maintained, with patients receiving a transfusion if haemoglobin concentration fell below 80 g/L, or if significant bleeding or haemodynamic instability occurred. The primary outcome was a composite of ischaemic event (myocardial infarction, permanent stroke, gut ischaemia or acute kidney injury) or serious infection (sepsis, endocarditis, respiratory tract or wound infection). Patients were followed for 12 weeks following surgery. Sixty-three (63) of 270 patients received a red cell transfusion (23.3%). Transfused patients had significantly lower body mass index (BMI), a higher proportion of females, a lower preoperative haemoglobin and haematocrit, a higher EuroSCORE II score, worse renal function and were more likely to have undergone urgent surgery compared to the unadjusted control cohort. Once matched, there was no difference in the primary outcome between cohorts. There was a significantly increased length of hospital stay in the transfused group (median 7 days transfused, median 5 days not-transfused, p=0.001). Red cell transfusion, using a transfusion threshold of 80 g/L, does not appear to be associated with adverse ischaemic or infective outcomes after aortic valve replacement.

MAGGIC, STS, and EuroSCORE II Risk Score Comparison After Aortic and Mitral Valve Surgery

To compare the Meta-Analysis Global Group in Chronic Heart Failure (MAGGIC) risk score with the established Society of Thoracic Surgeons (STS) and EuroSCORE II risk prediction models regarding mortality discrimination after aortic and mitral valve surgery. Retrospective cohort study. Single tertiary academic medical center. A total of 259 patients who underwent open aortic valve replacement or open mitral valve repair/replacement from 2009-2014. Retrospective chart review. MAGGIC, STS, and EuroSCORE II risk scores for each patient were studied using binary logistic regression and receiver operating characteristic analysis for the primary endpoint of one-year mortality and secondary endpoint of 30-day mortality. One-year mortality C-statistics were similar across risk scores (STS 0.709, 95% confidence interval [CI] 0.578-0.841; MAGGIC 0.673, 95% CI 0.547-0.799; EuroSCORE II 0.642, 95% CI 0.521-0.762; p = 0.56 between STS and MAGGIC; p = 0.20 between STS and EuroSCORE II; and p = 0.69 between MAGGIC and EuroSCORE II). Thirty-day mortality C-statistics also were similar between STS (0.797, 95% CI 0.655-0.939; p < 0.0001 v null hypothesis), MAGGIC (0.721, 95% CI 0.581-0.860; p = 0.33 v STS), and EuroSCORE II (0.688, 95% CI 0.557-0.818; p = 0.06 v STS; p = 0.68 v MAGGIC). The MAGGIC risk score performs similarly to STS and EuroSCORE II risk models in mortality discrimination after aortic and mitral valve surgery, albeit in a small sample size. This finding has important implications in establishing MAGGIC as a viable prognostic model in this population subset, with fewer variables and ease of use representing key advantages over STS and EuroSCORE II.

Transapical Transcatheter Valve Replacement Using J-Valve for Aortic Valve Diseases

The J-Valve system (Jie ChengMedical Technologies, Suzhou, China) is designed specifically for transapical transcatheter aortic valve replacement and has three U-shaped graspers. With the unique structure, the J-Valve is suitable for both aortic stenosis and aortic regurgitation. We used the J-Valve system for patients with aortic valve diseases and observed favorable results. From January 2018 to August 2019, 23 patients underwent transapical transcatheter valve replacement using the J-Valve system. High-risk patients with diseased peripheral vessels (small diameter, heavily calcified, and tortuous arteries), pure aortic regurgitation, and complex prosthetic valve-in-valve cases were enrolled. Ten patients mainly had aortic stenosis, 11 patients had pure aortic regurgitation, and 2 patients had valve-in-valve aortic valve position. The Society of Thoracic Surgeons and European System for Cardiac Operative Risk Evaluation average preoperative scores were 8.9% and 8.7%, respectively. The technique success rate was 91.3% (21 of 23; 1 patient was referred for open surgery and 1 patient received intraoperative valve-in-valve), and 1 patient died of cardiogenic shock after the procedure (mortality 4.3%, 1 of 22). One patient had stroke postoperatively and recovered well; no cases needed to undergo permanent pacemaker implantation. During the follow-up period, 1 patient died of acute heart attack. No moderate or severe paravalvular leakage was found. Transcatheter aortic valve replacement surgery with the J-Valve system is effective, even when it is traumatic and requires the transapical route. The applicability of the J-Valve system in pure aortic regurgitation patients is the advantage of this system.

Abstract 17231: Adult Protein Energy Malnutrition is an Independent Risk Factor With Increased Odds of Cardiogenic Shock in Patients With Infective Endocarditis Who Had Valve Replacement

Introduction: Protein Energy Malnutrition (PEM) is common among adults with chronic medical conditions, especially in patients with chronic heart, lung disease and malignancies. These conditions are associated with worse in hospital outcomes. However, the complex relationship between chronic medical conditions and PEM make the true effect of PEM on outcomes difficult to ascertain. This is compounded by the relative underdiagnosis of PEM in adults. Our study aimed to determine if PEM is an independent risk factor for adverse outcomes among patients with infective endocarditis (IE) who had mitral valve (MV) and /or aortic valve (AV) replacement surgery. Methods: Data was obtained from the National Inpatient Sample for 2016 &amp; 2017. Studied cohort were patients with IE who underwent AV and /or MV replacement. This group was divided by presence or absence of PEM using ICD-10 codes. Primary outcome was inpatient mortality. Secondary outcomes were total hospital charges, length of stay (LOS), NSTEMI, post procedural cardiac complications, acute kidney failure (AKI) and need for intra aortic balloon pump (IABP). Multivariate logistic and linear regression models were used to compare outcomes. Results: A total of 4275 hospitalizations met the inclusion criteria, of which about a fifth (20.12%) had PEM.Patients with PEM had higher adjusted odds of post procedural cardiogenic shock (aOR: 3.65, 95% CI: 1.724 - 7.746), and need for IABP placement (aOR: 4.01, 95% CI: 1.958 - 8.199), as well as significantly higher mean difference in total hospital charges and length of stay, relative to patients without PEM. There was however no significant difference in mortality, composite post procedural cardiac complications, NSTEMI or AKI between the PEM and non-PEM subgroup. Conclusion: PEM is associated with post procedural cardiogenic shock and intra-aortic balloon pump placement in patients with infective endocarditis who underwent valve replacement surgery but this impact did not translate to higher mortality. More research is needed to elucidate the role of PEM as a major comorbidity.

Transcatheter Aortic Valve Implantation: Where are we in 2020?

Abstract Aortic stenosis is an insidious disease of rapid progression after the onset of symptoms. Aortic valve replacement surgery is a well-established therapy that reduces symptoms and increases survival rates. However, the procedure may be associated with high operative mortality rates and promote comorbidity. Depending on the local reality, the prevalence of patients considered inoperable (due to medical comorbidities and age) may achieve 30%. For these patients, transcatheter aortic valve implantation (TAVI) was initially indicated; over time, the method has [...]

Long-term results after aortic valve replacement for bicuspid or tricuspid valve morphology in a Swedish population.

OBJECTIVESOur goal was to study long-term observed and relative survival after first-time aortic valve replacement surgery with or without concomitant coronary artery bypass surgery with reference to valve morphology (i.e. bicuspid vs tricuspid).METHODSConsecutive patients (n = 5086) from 3 Swedish hospitals, operated on between 1 January 2005 and 31 December 2016, were included. The 30-day mortality (n = 116, 2.3%) was excluded from the analysis of long-term observed and relative survival (n = 4970). Observed survival was analysed using Cox regression. Relative survival was calculated as the ratio between observed and expected survival based on data from the general Swedish population, matched for age, sex and calendar year. Risk factors for death were explored using multivariable analysis.RESULTSDuring the follow-up (median 4.7 years) period, 1157 (23%) patients died. Observed survival excluding 30-day mortality was 96.6%, 82.7% and 57.6% after 1, 5 and 10 years. Compared with the general Swedish population, the relative 1-, 5- and 10-year survival rates were 99.0%, 97.5% and 89.0%. Bicuspid morphology was independently associated with higher observed and relative long-term survival. Renal dysfunction, diabetes, chronic obstructive pulmonary disease, heart failure, smoking and atrial fibrillation were associated with higher long-term mortality. Combined surgery was not associated with higher observed or relative mortality.CONCLUSIONSPatients with a bicuspid morphology had better prognosis, matching that of the general population. With increased age, long-term relative survival compared favourably with survival in the general Swedish population. Adding coronary artery bypass surgery to an aortic valve replacement procedure did not affect long-term outcome.

Management of a Case of Aortic Valve Replacement with Left Ventricle Clot Removal Developing Acute Kidney Injury in Postoperative Period

AbstractCardiac surgery associated-acute kidney injury (AKI) is a common and a serious complication of cardiac surgery requiring cardiopulmonary bypass and it is the second most common cause of AKI in intensive care unit. Recently, two consensus conferences have suggested new diagnostic criteria to define AKI and risk score to better identify patients who will develop AKI after cardiac surgery. In fact, prompt recognition of high-risk patients could allow a more aggressive management at a reversible stage of an incoming ARF. In this case report, we have discussed a case of 21-year-old patient with bicuspid aortic valve with severe aortic stenosis with ejection fraction 15% and left ventricle (LV) clot undergoing surgery for aortic valve replacement with LV clot removal. In the postoperative period, he developed AKI that was managed successfully by early intervention by slow low efficiency dialysis and diafiltration and hemodialysis and patient discharged successfully from hospital.

Is this a bridge too far?

Maeda et al. present what may be the second reported case of transcatheter aortic valve replacement (TAVR) followed by staged open surgical aortic valve replacement (SAVR) in a high-risk patient. The authors propose that TAVR may serve as a bridge procedure before SAVR for aortic stenosis in selected younger patients with high surgical risk. Further experience may clarify how long to wait after TAVR to perform SAVR. Timing will be a balance between improving surgical risk versus increasing difficulty removing the prosthesis. Knowledge of TAVR durability will ultimately be needed to decide between "destination" TAVR versus bridging to SAVR with a more durable device.

Atrial matrix remodeling in atrial fibrillation patients with aortic stenosis

BackgroundThis study aimed to evaluate atrium extracellular matrix remodeling in atrial fibrillation (AF) patients with severe aortic stenosis, through histological fibrosis quantification and extracellular matrix gene expression analysis, as well as serum quantification of selected protein targets.MethodsA posthoc analysis of a prospective study was performed in a cohort of aortic stenosis patients. Between 2014 and 2019, 56 patients with severe aortic stenosis submitted to aortic valve replacement surgery in a tertiary hospital were selected.ResultsFibrosis was significantly increased in the AF group when compared to sinus rhythm (SR) patients (p = 0.024). Moreover, cardiomyocyte area was significantly higher in AF patients versus SR patients (p = 0.008). Conversely, collagen III gene expression was increased in AF patients (p = 0.038). TIMP1 was less expressed in the atria of AF patients. MMP16/TIMP4 ratio was significantly decreased in AF patients (p = 0.006). TIMP1 (p = 0.004) and TIMP2 (p = 0.012) were significantly increased in the serum of AF patients. Aortic valve maximum (p = 0.0159) and mean (p = 0.031) gradients demonstrated a negative association with serum TIMP1.ConclusionsAtrial fibrillation patients with severe aortic stenosis present increased atrial fibrosis and collagen type III synthesis, with extracellular matrix remodelling demonstrated by a decrease in the MMP16/TIMP4 ratio, along with an increased serum TIMP1 and TIMP2 proteins.

Body mass index is associated with low postoperative cardiac output in patients undergoing aortic valve replacement.

Overweight and obesity (O/O) generate lipotoxicity of the cardiac fiber and increase the incidence and progression of aortic valve stenosis. The low cardiac output syndrome (LCOS) is a timing complication after to aortic valve replacement (AVR) surgery. The objective of the study was to investigate if body mass index (BMI) kg/m2 is a risk factor associated with LCOS and mortality in the post-operative period of AVR. A historic cohort study was designed, including patients with severe aortic stenosis (SAS), who were subjected to AVR. 152 patients were included, 45 (29.6%), with normal weight (NW), 60 were overweight (39.5%), and 47 obese (30.9%). The prevalence of systemic hypertension (HT) was higher in O/O (p < 0.0001). Incidence of LCOS was 44.7%, being more frequent in the O/O groups compared to the NW group, 43.3%, 68.1%, and 22.2%, respectively, (p < 0.05 in overweight and p < 0.0001 in the obese). Assessing the presence or absence of LCOS associated with BMI as a numerical variable, we found that women, HT, BMI, left ventricular mass, and valve size, were associated with LCOS (p < 0.02, p < 0.02, p < 0.001, p < 0.032, and p < 0.045, respectively). Mortality was higher in patients who had LCOS (p < 0.02). Multivariate model showed that BMI was an independent risk factor for LCOS (odds ratio [OR] 1.21 [95% CI 1.08-1.35], p < 0.001). BMI is a risk factor associated to LCOS in the post-operative period of AVR in patients with SAS.

Double-lumen oropharyngeal cannula for sedation in percutaneous aortic valve implant with transesophageal echocardiography. Case report

Introduction The prevalence and severity of aortic valve disease increases in the elderly population. Transfemoral transcatheter aortic valve implantation (TAVI) has been gaining space as an alternative method even in mild cases to conventional open aortic valve replacement surgery. In many centers, conscious sedation as an alternative to general anesthesia to these procedures. Therefore, the use transesophageal echocardiography (TEE) is a concern when conscious sedation is performed. In this case report, we describe for the first time the use of a double-lumen oropharyngeal cannula to support sedation in a patient undergoing TAVI and TEE monitoring. Methods Case report: 72-year-old male patient, 58kg, 178 cm tall, physical status ASA 3, Euroescore II 1,81%, with severe aortic stenosis (Aortic valve orifice area = 0.5cm2, maximum and mean gradient = 58mmHg and 31mmHg, respectively) underwent elective percutaneous aortic valve implantation with transfemoral vascular access. After standard monitoring, sedation was started with intravenous infusion of dexmedetomidine and propofol titrated to effect. The cannula was inserted right after loss of consciousness, connecting one of its lines to the capnograph and the other one to the supplemental oxygen source with a continuous flow of 3L/min. Right after, TEE probe was passed through the cannula to the upper esophagus.(Figure 1) A: CO2 exhaled line monitoring; B: O2 line administration; C: Lumen used to keep a better patency of the airway during spontaneous ventilation; D: Lumen used to pass the TEE probe. Throughout the procedure, patient was maintained on spontaneous ventilation, maintaining BIS values below 60. Data collection includes: ETCO2, mean arterial pressure, heart rate, BIS values, SatO2 and arterial blood gases . The examiner was also questioned subjectively the comfort of handling the TEE probe during the exam (easy, moderate or difficult) and also checking for possible oral cavity trauma due use of the cannula during procedure. Results The procedure went without any complications. No soft tissue lesions were found The examiner considered the handling of the probe with the presence of the cannula easy. Discussion The oropharyngeal cannula was feasible to support sedation in this patient for TAVI with TEE monitoring. However, further studies with a larger number of patients and randomized trials comparing different techniques are still needed to confirm our results.

Adverse remodeling in atrial fibrillation following isolated aortic valve replacement surgery.

Atrial fibrillation (AF) is the most common arrhythmia with adverse clinical outcomes. Aortic valve replacement (AVR) is one of the most frequently performed cardiac surgeries, although there is scarce evidence on arrhythmic outcomes. We aimed to evaluate AF during the first year post- isolated aortic valve replacement surgery and its clinical, analytical, and echocardiographic predictors. Severe aortic stenosis patients with no prior atrial fibrillation submitted to isolated aortic valve replacement surgery were included in our study, of which 316 remained in sinus rhythm and 24 developed AF. We performed logistic regression searching for AF predictors and a longitudinal comparison between pre and post-operative echocardiographic data. Postoperative AF (POAF), diabetes, and follow-up indexed Left Atrium Diameter (iLAD) were significantly higher in the group of patients developing AF. POAF and iLAD were independent AF predictors at follow-up. No differences between groups were found regarding baseline and follow-up echocardiographic data except for indexed Left Ventricle End-diastolic Diameter (LVED), which failed to decrease after surgery in the AF group. POAF and iLAD independently predicted AF at 1 year following isolated AVR surgery in aortic stenosis patients with no AF history. iLVED did not decrease significantly at follow-up in AF patients, possibly reflecting adverse ventricular remodeling.

Early Valve Replacement for Severe Aortic Valve Disease: Effect on Mortality and Clinical Ramifications.

Timing of aortic valve intervention for chronic aortic regurgitation (AR) and/or aortic stenosis (AS) potentially affects long-term survival. The 2014 American Heart Association/American College of Cardiology (AHA/ACC) guidelines provide recommendations for the timing of intervention. Subsequent to the guidelines’ release, several studies have been published that suggest a survival benefit from earlier timing of surgery for severe AR and/or AS. The aim of this review was to determine whether patients who have chronic aortic regurgitation (AR) and/or aortic stenosis (AS) have a survival benefit from earlier timing of aortic valve surgery. Medical databases were systematically searched from January 2015 to April 2020 for randomized controlled trials (RCTs) and observational studies that examined the timing of aortic valve replacement surgery for chronic AR and/or AS. For chronic AR, four observational studies and no RCTs were identified. For chronic AS, five observational studies, one RCT and one meta-analysis were identified. One observational study examining mixed aortic valve disease (MAVD) was identified. All of these studies, for AR, AS, and MAVD, found long-term survival benefit from timing of aortic valve surgery earlier than the current guidelines. Larger prospective RCTs are required to evaluate the benefit of earlier surgical intervention.

Blood management in a patient with anti-Oka antibody who underwent cardiac surgery using cardiopulmonary bypass: a case report

BackgroundCardiac surgery under cardiopulmonary bypass (CPB) is often associated with massive bleeding and blood transfusion. For patients requiring specific blood products, meticulous blood management is critical to reduce blood loss, as well as the need for transfusion. Here, we have described the intraoperative blood management in a patient with anti-Oka antibody, who underwent cardiac surgery with CPB.Case presentationA 79-year-old woman was scheduled for open aortic valve replacement and tricuspid valve annuloplasty under hypothermic CPB. Her blood type was A RhD(+) Ok(a−), and anti-Oka, an extremely rare antibody against erythrocyte antigen, was detected. Eight units of Ok(a−) frozen thawed red cells (FTRCs), and six units of red blood cells donated by three Ok(a−) individuals were collected just prior to surgery. Although she was anemic, acute normovolemic hemodilution was conducted after anesthesia induction to preserve the autologous whole blood. Four units of FTRCs were loaded in the CPB priming solution, and modified ultrafiltration was adopted during CPB to prevent further hemodilution. After CPB termination, two units of FTRCs, four units of fresh frozen plasma, and ten units of platelet concentrate were intensively transfused, facilitating surgical hemostasis and stable hemodynamics. The autologous whole blood was returned to the patient in the intensive care unit. Since the hemoglobin and hematocrit levels were maintained postoperatively, no additional transfusion was required throughout her hospital stay.ConclusionsMultidisciplinary intraoperative blood management in a patient with anti-Oka antibody facilitated successful cardiac surgery using CPB, along with effective use of limited blood products.

Aort Kapak Replasmanı Cerrahisinde Dikişsiz Kapaklar ile Konvansiyonel Kapakların Perioperatif Sonuçlarının Karşılaştırılması

Aort Kapak Replasmanı Cerrahisinde Dikişsiz Kapaklar ile Konvansiyonel Kapakların Perioperatif Sonuçlarının Karşılaştırılması

Influence of surgical volume on outcomes in low-risk patients undergoing isolated surgical aortic valve replacement

BackgroundIntermediate- and high-risk patients undergoing isolated surgical aortic valve replacement have superior outcomes at higher-volume compared with lower-volume hospitals. This study examines the impact of hospital volume on outcomes in low-risk patients undergoing aortic valve replacement. MethodsUsing data from our 29 North Texas hospital collaborative, we examined 2066 low-risk cases (Society of Thoracic Surgeons Predicted Risk of Mortality of ≤3%) undergoing aortic valve replacement surgery between January 1, 2012, and December 31, 2017. Cases from 3 high-volume hospitals (≥200 aortic valve replacement cases total) and 26 low-volume hospitals (<200 cases total) were examined. ResultsSome 53.5% of the cases were at high-volume hospitals. No statistical differences were seen in the Predicted Risk of Mortality or pertinent demographics between the high-volume and low-volume hospitals. Significant differences in outcomes were seen between the 2 groups in operative mortality (2.28% vs 1.19%, P = .007), renal failure (2.14% vs 1.00%, P = .003), and readmission within 30 days (9.72% vs 6.25%, P < .001) when comparing low-volume with high-volume hospitals. In patients undergoing aortic valve replacement, undergoing the procedure in a low-volume hospital was an independent predictor for operative mortality (odds ratio, 1.95; 95% confidence interval, 1.20-3.20; P = .008) and renal failure (odds ratio, 2.25; 95% confidence interval, 1.33-3.81; P = .003). ConclusionsOperative mortality in low-risk patients undergoing aortic valve replacement is higher in low-volume compared with high-volume hospitals. The probability of a major complication, such as renal failure, is also greater in low-volume hospitals. The relationship between volume and outcomes in low-risk patients will require more research to understand the causes and design appropriate interventions.

A Case of Whipple's Disease Related Infectious Endocarditis

Whipple's disease is caused by Tropheryma whipplei and is known to have protean clinical presentation which could be influenced by patient's immunologic and genetic features. In contemporary literature abundant amount of data could be found on extensive prevalence of infectious endocarditis caused by Tropheryma whipplei . This article presents history of a patient who was observed because of ischemic heart disease, angina pectoris, myocardial infarction, possible ischemic cardiomyopathy and in whom infectious endocarditis complicated by severe aortic regurgitation needing aortic valve replacement surgery was eventually diagnosed. Our patient did not meet Duke criteria, which is a sign of infectious endocarditis caused by Tropheryma whipplei , but a thorough analysis of the disease course, clinical features, heart ultrasound and clinical improvement on specific therapy against Tropheryma whipple i aroused our suspicion, and morphological and bacteriological analysis of the involved (excised) valve, confirmed the diagnosis of Whipple disease. The article presents differential diagnostic criteria of aortic insufficiency and possible causes of coronary insufficiency in the absence of marked coronary atherosclerosis.