Preintervention imaging and intraoperative management care of the hypertrophic obstructive cardiomyopathy patient.

With an estimated overall mortality of less than 1 percent per year, hypertrophic cardiomyopathy, is the most common genetic cardiomyopathy. Intraoperative transesophageal echocardiography is the standard of care for assessing patients with hypertrophic obstructive cardiomyopathy undergoing surgical septal myectomy, allowing surgical planning, intraoperative hemodynamic monitoring, and postprocedural assessment of the repair, including detection of immediate complications. At various phases during surgical septal myectomy, the changing hemodynamic conditions may lead to worsening or improvement in left ventricle outflow tract obstruction by change in preload or afterload, systolic anterior motion of the mitral valve, or sympathetic stimulation. These characteristics represent unique challenges in the management of these patients, requiring a comprehensive understanding of the management of all the conditions required to decrease the left ventricle outflow tract gradient avoiding obstruction, which include the maintenance of sinus rhythm, adequate rate avoiding tachycardia and bradycardia, and avoidance of systemic hypotension preserving preload and afterload, with adequate vasoactive agents. The aim of this review is to summarize the perioperative assessment and management of patients undergoing hypertrophic obstructive myopathy surgery.

Hypertrophic Obstructive Cardiomyopathy: Discrepancy Between Hemodynamic Measurements in the Cardiac Laboratory and Operating Room Is to Be Expected.

OBJECTIVES: It is not uncommon to observe some discrepancy in hemodynamic values characterizing left ventricular outflow tract (LVOT) obstruction preoperatively and in the operating room in patients with hypertrophic obstructive cardiomyopathy. Interpretation of this discrepancy can be challenging. To clarify the extent of the discrepancy, the authors compared hemodynamic variables in patients undergoing septal myectomy at the time of preoperative and intraoperative evaluation. DESIGN: Retrospective study. SETTING: Single academic medical center. INTERVENTIONS: Medical records review, study group-173 patients. MEASUREMENTS AND MAIN RESULTS: While there was no statistically significant difference in resting peak LVOT gradients by preoperative transthoracic echocardiography (TTE) compared to intraoperative transesophageal echocardiography (46 mmHg [19-87 mmHg] v 36 mmHg [16-71 mmHg], p = 0.231), the former were higher compared to direct needle-resting LVOT gradient measurements before myectomy (49 mmHg [19-88 mmHg] v 32 mmHg [14-67 mmHg], p = 0.0022). The prevalence of systolic anterior motion was high (94.6% v 91.6%, P = 1.000) both on pre- and intraoperative evaluation. The incidence of moderate/severe mitral was higher intraoperatively (p < 0.0001). Pulmonary artery systolic pressures measured by pulmonary artery catheter provided higher values compared to preoperative TTE estimate (39 mmHg [34-45 mmHg] v 34 mmHg [28-41 mmHg], p < 0.0001). CONCLUSIONS: Discrepancy between hemodynamic measurements in the cardiac laboratory and operating room is common and generally should not affect planned patients' care. These changes in hemodynamics might be explained by preoperative fasting, anesthetic agents, volume shifts while supine, and positive-pressure ventilation, as well as the difference in measurement techniques.

Impact of Aortic Valve Replacement for Severe Aortic Stenosis on Perioperative Outcomes Following Major Noncardiac Surgery.

OBJECTIVE: To compare the incidence of major adverse cardiac events and death among severe aortic stenosis patients with and without aortic valve replacement (AVR) before noncardiac surgery. PATIENTS AND METHODS: We retrospectively evaluated 491 severe aortic stenosis patients undergoing non-emergency/non-urgent elevated-risk noncardiac surgery between January 1, 2000, and December 31, 2013, including 203 patients (mean age, 74±10 years, 63.5% men) with previous AVR and 288 patients (mean age, 77±12 years, 55.6% men) without prior AVR. RESULTS: The incidence of major adverse cardiac events was significantly lower in the AVR group (5.4% vs 20.5%; P<.001), primarily because of the lower incidence of new or worsening heart failure (2.5% vs 17.7%; P<.001), compared with the non-AVR group. No significant differences were observed between the groups with and without AVR in the incidence of death (2.5% vs 3.5%; P=.56), myocardial infarction (0.5% vs 1.4%; P=.48), ventricular arrhythmia (0.0% vs 0.7%; P=.51), or stroke (0.0% vs 0.7%; P=.51) at 30-days. At a median follow-up of 4.2 (interquartile range,1.3-7.5) years, overall mortality was significantly worse in patients without versus with AVR (5-year rate: 57.0% vs 32.7%; P<.001). Symptomatic patients without AVR (n=35) had the worst outcomes overall, including increased 30-day and overall mortality rates, compared with the AVR-group and asymptomatic non-AVR patients. CONCLUSION: In patients with severe aortic stenosis, AVR before noncardiac surgery was associated with decreased incidence of heart failure after noncardiac surgery and improved overall survival without differences in 30-day survival, myocardial infarction, ventricular arrhythmia, or stroke. Preoperative AVR should be considered in symptomatic patients for whom the benefit of AVR is greatest.

Left ventricular ejection hemodynamics before and after relief of outflow tract obstruction in patients with hypertrophic obstructive cardiomyopathy and valvular aortic stenosis.

OBJECTIVE: There has been debate on the importance and pathophysiologic effects of the dynamic subaortic pressure gradient in hypertrophic obstructive cardiomyopathy. The study was conducted to elucidate the hemodynamic abnormalities associated with the dynamic pressure gradient in hypertrophic obstructive cardiomyopathy. METHODS: Eight patients with hypertrophic obstructive cardiomyopathy and 7 patients with valvular aortic stenosis underwent a detailed hemodynamic study of pressure flow relationships before and after myectomy or aortic valve replacement during operation. RESULTS: In aortic stenosis, the increased gradient after premature ventricular contraction was associated with an increase in peak flow (325 ± 122 mL/s to 428 ± 147 mL/s, P = .002) and stroke volume (75.0 ± 27.3 mL to 88.0 ± 24.0 mL, P = .004), but in hypertrophic obstructive cardiomyopathy peak flow remained unchanged (289 ± 79 mL/s to 299 ± 85 mL/s, P = .334) and stroke volume decreased (45.9 ± 18.7 mL to 38.4 ± 14.4 mL, P = .04) on the postpremature ventricular contraction beat. After myectomy, the capacity to augment stroke volume on the postpremature ventricular contraction beats was restored in patients with hypertrophic obstructive cardiomyopathy (45.6 ± 14.4 mL to 54.4 ± 11.8 mL, P = .002). CONCLUSIONS: The pressure flow relationship in hypertrophic obstructive cardiomyopathy supports the concept of true obstruction to outflow, with a low but continued flow during late systole, when the ventricular-aortic pressure gradient is the highest. Septal myectomy can abolish obstruction and restore the ability to augment stroke volume, which may explain the mechanism of symptomatic improvement after operation.

Accuracy of Jet Direction on Doppler Echocardiography in Identifying the Etiology of Mitral Regurgitation in Obstructive Hypertrophic Cardiomyopathy.

BACKGROUND: Mitral valve regurgitation (MR) mediated by systolic anterior motion (SAM) in obstructive hypertrophic cardiomyopathy (HCM) is traditionally characterized by a posteriorly directed jet on Doppler echocardiography. Many believe that MR in the absence of a posteriorly directed jet signals the presence of intrinsic mitral valve (MV) disease. METHODS: A total of 709 adult patients with obstructive HCM who underwent septal myectomy were evaluated; 330 of these patients had >2 + MR preoperatively and constituted the study group. SAM-mediated MR was defined as MR that was eliminated or substantially reduced by myectomy for relief of left ventricular outflow tract obstruction with no need for MV intervention. RESULTS: On preoperative transthoracic echocardiography, 168 of 258 patients with SAM-mediated MR and nine of 28 patients with intrinsic MV disease had isolated posterior jets, corresponding to sensitivity and specificity of 65.1% and 67.9% for identifying SAM-mediated MR; the positive predictive value was 94.9% and the negative predictive value was 17.4%. On prebypass transesophageal echocardiography, 169 of 284 patients with SAM-mediated MR and five of 28 patients with intrinsic MV disease had isolated posterior jets, corresponding to sensitivity and specificity of 59.5% and 82.1%; the positive predictive value and negative predictive value were 97.1% and 16.7%. CONCLUSION: A posteriorly directed jet of MR in obstructive HCM correlates highly with SAM as the underlying pathophysiologic mechanism, but because of the low negative predictive value, clinicians should be cautious in using the jet direction of MR on preoperative transthoracic echocardiography to guide the decision for concomitant MV surgery during septal myectomy for HCM.

Improving outcome of valve replacement for carcinoid heart disease.

OBJECTIVE: Carcinoid heart disease is characterized by tricuspid valve regurgitation and varying degrees of pulmonary valve regurgitation or stenosis. Valve replacement procedures may be complicated by systemic effects of carcinoid syndrome, as well as hepatic dysfunction and right heart failure. This study was performed to identify factors that might be associated with improving early mortality rates and late outcomes. METHODS: Between November 1985 and January 2018, 240 adult patients underwent surgery for carcinoid heart disease at the Mayo Clinic. We analyzed the association of multiple clinical and echocardiographic variables on early mortality and late survival. RESULTS: The median (interquartile range) age of patients was 63 years (55-69), and 117 patients (49%) were male. Before operation, 157 patients (70%) had New York Heart Association class III or IV limitation. Somatostatin analogs were used in 221 patients (92%), and long-acting somatostatins were used in 130 patients (54%). Loop diuretic therapy was used preoperatively in 125 patients (52%). Early mortality rate was 29% (9/22) between 1985 and 1994, but decreased to 7% (6/81) during 1995 to 2004, and to 5% (7/128) from 2005 onward. Overall survival estimates at 1, 3, and 5 years were 69%, 48%, and 34%, respectively. Older age, advanced New York Heart Association class, and a nonlinear effect of creatinine were independently associated with overall mortality. CONCLUSIONS: Valve replacement for carcinoid heart disease has acceptable short-term mortality, and early risk has decreased in the current era. Earlier intervention may improve overall survival.

Acute aortitis of the ascending aorta.

We report a rare presentation of focal non-aneurysmal aortitis with mural thrombus of the ascending aorta. This was successfully treated with surgical resection and intravenous antibiotics. Pathology of the surgical specimen suggests that this was likely infectious aortitis, but the source of infection has not been identified.

Mitral Regurgitation in Patients With Hypertrophic Obstructive Cardiomyopathy: Implications for Concomitant Valve Procedures.

BACKGROUND: Incidence and outcome of mitral valve (MV) surgery are unknown in patients with hypertrophic obstructive cardiomyopathy (HOCM) undergoing extended transaortic septal myectomy. OBJECTIVES: This study sought to define indications and suitable operative strategy for mitral regurgitation (MR) in patients with HOCM. METHODS: A total of 2,107 septal myectomy operations performed in adults from January 1993 to May 2014 at Mayo Clinic in Rochester, Minnesota, were retrospectively reviewed. Patients with prior MV operation and apical hypertrophic cardiomyopathy were excluded. Overall, 2,004 operations were performed in 1,993 patients. RESULTS: Pre-operative MR was grade ≥3 (of 4) in 1,152 operations (57.5%). Systolic anterior motion of mitral leaflets caused the MR in most patients. However, intrinsic MV disease was identified pre-operatively in 99 patients, all of whom had MV surgery (with septal myectomy). In 1,905 operations, no intrinsic MV disease was identified pre-operatively; in 1,830 (96.1%), septal myectomy was performed without a direct MV procedure. For 75 patients, intrinsic MV disease discovered intraoperatively led to concomitant MV repair (86.7%) or replacement (13.3%). After isolated septal myectomy, the percentage of patients with MR grade ≥3 decreased from 54.3% to 1.7% (p = 0.001) on early post-operative echocardiography. Among 174 patients with concomitant MV surgery, late survival was superior with MV repair (n = 133 [76.4%]) versus replacement (10-year survival: 80.0% vs. 55.2%; p = 0.002). CONCLUSIONS: In most patients with HOCM, MR related to systolic anterior motion of the MV is relieved through adequate myectomy. Concomitant MV surgery is rarely necessary unless intrinsic MV disease is present. When MV procedures are required, repair is preferred because of improved survival compared with replacement.

Mitral stenosis and hypertrophic obstructive cardiomyopathy: An unusual combination.

OBJECTIVE: Systolic anterior motion of mitral valve (MV) leaflets is a main pathophysiologic feature of left ventricular outflow tract (LVOT) obstruction in hypertrophic obstructive cardiomyopathy. Thus, restricted leaflet motion that occurs with MV stenosis might be expected to minimize outflow tract obstruction related to systolic anterior motion. METHODS: From January 1993 through February 2015, we performed MV replacement and septal myectomy in 12 patients with mitral stenosis and hypertrophic obstructive cardiomyopathy at Mayo Clinic Hospital in Rochester, Minn. Preoperative data, echocardiographic images, operative records, and postoperative outcomes were reviewed. RESULTS: Mean (standard deviation) age was 70 (7.6) years. Preoperative mean (standard deviation) maximal LVOT pressure gradient was 75.0 (35.0) mm Hg; MV gradient was 13.7 (2.8) mm Hg. From echocardiographic images, 4 mechanisms of outflow tract obstruction were identified: systolic anterior motion without severe limitation in MV leaflet excursion, severe limitation in MV leaflet mobility with systolic anterior motion at the tip of the MV anterior leaflet, septal encroachment toward the LVOT, and MV displacement toward the LVOT by calcification. Mitral valve replacement and extended septal myectomy relieved outflow gradients in all patients, with no death or serious morbidity. CONCLUSIONS: Patients with mitral stenosis and hypertrophic obstructive cardiomyopathy have multiple LVOT obstruction mechanisms, and MV replacement may not be adequate treatment. We favor septal myectomy and MV replacement in this complex subset of hypertrophic obstructive cardiomyopathy.

Safety of Noncardiac Surgery in Patients With Hypertrophic Obstructive Cardiomyopathy at a Tertiary Care Center.

OBJECTIVES: This study's purpose was to review non-cardiac surgery (NCS) in patients with hypertrophic obstructive cardiomyopathy (HOCM) to examine perioperative management and quantify postoperative mortality and worsening heart failure. DESIGN: Retrospective review. SETTING: A single tertiary care center. PARTICIPANTS: The study included 57 adult patients with HOCM who underwent NCS from January 1, 1996, through January 31, 2014. INTERVENTIONS: Noncardiac surgery. MEASUREMENTS AND MAIN RESULTS: The authors identified 57 HOCM patients who underwent 96 NCS procedures. Vasoactive medications were administered to the majority of NCS patients. Three patients (3%) died within 30 days of NCS, but causes of death did not appear to be cardiac in nature. Death after NCS was not significantly associated with preoperative left ventricular ejection fraction (p = 0.2727) or peak instantaneous systolic resting gradient (0.8828), but was associated with emergency surgery (p = 0.0002). Three patients experienced worsening heart failure postoperatively, and this was significantly associated with preoperative New York Heart Association Class III-IV symptoms compared with I-II symptoms (p = 0.0008). CONCLUSIONS: HOCM patients safely can undergo NCS at multidisciplinary centers experienced in caring for these patients. The mortality rate in this study was less than that reported in the majority of other studies. Postoperative complications, including increasing heart failure, may occur, especially in patients with more severe preoperative cardiac symptoms.

Early and Late Outcomes of Surgical Treatment in Carcinoid Heart Disease.

BACKGROUND: Symptoms and survival of patients with carcinoid syndrome have improved, but development of carcinoid heart disease (CaHD) continues to decrease survival. OBJECTIVES: This study aimed to analyze patient outcomes after valve surgery for CaHD during a 27-year period at 1 institution to determine early and late outcomes and opportunities for improved patient care. METHODS: We retrospectively studied the short-term and long-term outcomes of all consecutive patients with CaHD who underwent valve replacement at our institution between 1985 and 2012. RESULTS: The records of 195 patients with CaHD were analyzed. Pre-operative New York Heart Association class was III or IV in 125 of 178 patients (70%). All had tricuspid valve replacement (159 bioprostheses, 36 mechanical), and 157 underwent a pulmonary valve operation. Other concomitant operations included mitral valve procedure (11%), aortic valve procedure (9%), patent foramen ovale or atrial septal defect closure (23%), cardiac metastasectomies or biopsy (4%), and simultaneous coronary artery bypass (11%). There were 20 perioperative deaths (10%); after 2000, perioperative mortality was 6%. Survival rates (95% confidence intervals) at 1, 5, and 10 years were 69% (63% to 76%), 35% (28% to 43%), and 24% (18% to 32%), respectively. Overall mortality was associated with older age, cytotoxic chemotherapy, and tobacco use; 75% of survivors had symptomatic improvement at follow-up. Presymptomatic valve operation was not associated with late survival benefit. CONCLUSIONS: Operative mortality associated with valve replacement surgery for CaHD has decreased. Symptomatic and survival benefit is noted in most patients when CaHD is managed by an experienced multidisciplinary team.

Aortic Stenosis and Noncardiac Surgery: Managing the Risk.

Managing the risk of noncardiac surgery in patients with aortic stenosis is a problem that is frequently confronted in clinical practice. Traditionally, patients with severe aortic stenosis were considered to be at substantial risk during noncardiac surgery, and as such, elective procedures were avoided before intervention on the aortic valve in most patients other than those who were ineligible or refused aortic valve replacement. Recent data suggest that with contemporary anesthesia and surgical techniques, the risk of noncardiac surgery is substantially lower than previously believed. We review the existent literature in the field, and propose a practical approach to complex patients.

Residual and recurrent gradients after septal myectomy for hypertrophic cardiomyopathy-mechanisms of obstruction and outcomes of reoperation.

OBJECTIVE: The aims of the present study were to identify the mechanisms of residual or recurrent left ventricular outflow tract obstruction in patients undergoing repeat septal myectomy for hypertrophic cardiomyopathy and to assess the early and late results of reoperation. METHODS: From January 1980 to June 2012, we performed 52 repeat myectomies in 51 patients. We reviewed the medical records and preoperative transthoracic echocardiograms to evaluate the adequacy of the previous resection and mechanism of left ventricular outflow tract obstruction. The complications of previous and repeat myectomy, New York Heart Association class, and survival were analyzed. RESULTS: The mean interval from previous myectomy to reoperation was 43 ± 51 months. In 6 patients (12%) residual or recurrent gradients were caused by isolated midventricular obstruction. In the remaining 46 operations, the mechanism of residual or recurrent gradients was identified as systolic anterior motion of mitral valve-related subaortic obstruction caused by inadequate length of previous subaortic septal excision in 31 patients (59% of the total), both an inadequate length and an inadequate depth of septectomy in 13 patients (25%), and both residual subaortic obstruction due to systolic anterior motion of the mitral valve and midventricular obstruction in 2 patients (4%). Preoperatively, 96% of patients were in New York Heart Association class III or IV; postoperatively, 93.8% were in class I or II (P < .001). The 10-year survival after reoperation was 98% and similar to that of an age- and gender-matched Minnesota population (P = .46). CONCLUSIONS: The most common cause of recurrent left ventricular outflow tract obstruction and symptoms in patients undergoing septal myectomy has been an inadequate length of septal excision. Reoperation is safe, with excellent long-term survival and functional improvement.

Perioperative risk of major non-cardiac surgery in patients with severe aortic stenosis: a reappraisal in contemporary practice.

AIMS: Severe aortic stenosis (SAS) is a major risk factor for death after non-cardiac surgery, but most supporting data are from studies over a decade old. We evaluated the risk of non-cardiac surgery in patients with SAS in contemporary practice. METHODS AND RESULTS: SAS patients (valve area ≤1 cm(2), mean gradient ≥40 mmHg or peak aortic velocity ≥4 m/s) undergoing intermediate or high-risk surgery were identified from surgical and echo databases of 2000-2010. Controls were matched for age, sex, and year of surgery. Post-operative (30 days) death and major adverse cardiovascular events (MACE), including death, stroke, myocardial infarction, ventricular tachycardia/fibrillation, and new or worsening heart failure, and 1-year survival were determined. There were 256 SAS patients and 256 controls (age 76 ± 11, 54.3% men). There was no significant difference in 30-day mortality (5.9% vs. 3.1%, P = 0.13). Severe aortic stenosis patients had more MACE (18.8% vs. 10.5%, P = 0.01), mainly due to heart failure. Emergency surgery, atrial fibrillation, and serum creatinine levels of >2 mg/dL were predictors of post-operative death by multivariate analysis [area under the curve: 0.81, 95% confidence intervals: 0.71-0.91]; emergency surgery was the strongest predictor of 30-day mortality for both SAS and controls. Severe aortic stenosis was the strongest predictor of 1-year mortality. CONCLUSION: Severe aortic stenosis is associated with increased risk of MACE. In contemporary practice, perioperative mortality of patients with SAS is lower than previously reported and the difference from controls did not reach statistical significance. Emergency surgery is the strongest predictor of post-operative death. These results have implications for perioperative risk assessment and management strategies in patients with SAS.

Transapical approach to myectomy for midventricular obstruction in hypertrophic cardiomyopathy.

BACKGROUND: Midventricular obstruction in hypertrophic cardiomyopathy (HCM) is less common than subaortic obstruction, and there are few data on outcomes after surgical treatment. METHODS: We reviewed 56 consecutive patients (28 men) with HCM and midventricular obstruction who underwent myectomy between February 1997 and June 2012. Five patients had prior myectomy for subaortic obstruction. Mean age was 42 ± 17 years. Preoperatively, 51% of patients had dyspnea, and the remaining had palpitations (25%), angina (5%), or syncope (9%). RESULTS: Midventricular obstruction was relieved by means of a transaortic myectomy in 5 patients, a transapical approach in 32 patients, and combined transaortic and transapical incisions in 19 patients. In 13 patients, an apical aneurysm or pouch was repaired at the time of midventricular myectomy. There were no early deaths. Intraoperative intraventricular gradients were reduced from 64 ± 32 mm Hg before myectomy to 6 ± 12 mm Hg postoperatively (p ≤ 0.0001). Early complications included atrial arrhythmias in 5 patients and reoperation for bleeding in 4 patients. Fifty patients had follow-up beyond 30 days (median, 1.6 years; range, 33 days to 13 years). Survival at 1 and 5 years was 100% and 95%, and average New York Heart Association class improved from 2.9 ± 0.7 preoperatively to 1.3 ± 0.6 postoperatively (p = 0.0001). There were no aneurysms related to the apical incision; 2 patients had late reoperation, 1 for resection of right atrial mass to prevent embolus. CONCLUSIONS: A transapical approach allows excellent exposure for midventricular myectomy and relief of intraventricular gradients and related symptoms. There were no complications unique to the apical incision, and 5-year survival was similar to expected survival (95% versus 97%).

Cold agglutinins in patients undergoing cardiac surgery requiring cardiopulmonary bypass.

OBJECTIVES: Cold agglutinins (CA) are circulating autoantibodies present in most humans. They are active below normal body temperatures. Cold hemagglutinin disease involves the presence of CA sufficiently active at temperatures in the periphery to produce hemolysis or agglutination. Systemic hypothermia and cold cardioplegia may result in agglutination or hemolysis. We reviewed the experience of a large referral center in managing patients with CA and cold hemagglutinin disease undergoing cardiac surgery requiring cardiopulmonary bypass. METHODS: The electronic medical records from 2002 to 2010 were searched to identify patients with CA or cold hemagglutinin disease who underwent cardiac surgery requiring cardiopulmonary bypass. Information related to preoperative CA testing and treatment, surgery, cardiopulmonary bypass, postoperative complications, and mortality was recorded. RESULTS: Sixteen patients underwent 19 procedures requiring cardiopulmonary bypass. Six patients had cold hemagglutinin disease. The identification of CA was made intraoperatively in 3 patients. One patient underwent preoperative plasma exchange. Cold blood cardioplegia was used in 2 of 16 procedures using cardioplegia, with the remaining using warmer blood cardioplegia. The lowest recorded intraoperative core temperature was less than 34 °C in 1 case. CA-related postoperative hemolysis requiring transfusion was present in 1 patient, which was resolved with active warming. No patient had evidence of permanent myocardial dysfunction, had a neurologic event, required dialysis, or died within 30 days. CONCLUSIONS: All patients with CA/cold hemagglutinin disease at the Mayo Clinic College of Medicine safely underwent cardiac surgery without major adverse morbidity or mortality. Patients with CA but without evidence of cold hemagglutinin disease can safely undergo normothermic cardiopulmonary bypass at 37°C and warm cardioplegia without further testing. Patients with cold hemagglutinin disease should undergo laboratory testing including CA titers and thermal amplitude and hematology consultation before cardiac surgery.

Increased risk of acute kidney injury in patients undergoing tricuspid valve surgery.

OBJECTIVES: We aimed to determine which patients undergoing tricuspid valve (TV) surgery are at increased risk for acute kidney injury (AKI). METHODS: We reviewed 951 patients [mean age 67 ± 13 years, 573 (60%) female] having TV surgery between 2000 and 2007. Analysis focused on clinical outcome; AKI was defined by the consensus RIFLE criteria (risk, injury, failure). RESULTS: Surgical procedures included isolated TV surgery in 224 (24%) and TV surgery in conjunction with another cardiac operation in 727 (76%) patients. TV surgery involved redo surgery in 395 (42%). The incidence of postoperative AKI was 30% (n = 285), and 75 (7.9%) of these patients required renal replacement therapy. AKI stratified by increased RIFLE class was associated with worse postoperative outcomes (prolonged intubation, length of hospital stay and mortality; P < 0.001 for each variable). For patients with AKI, odds ratio for mortality was 4.2 [95% confidence interval (CI) 3.2-5.4, P < 0.001; area under receiver operating curves 0.85 (95% CI 0.80-0.91)], and 2.3 (95% CI 1.9-2.9, P < 0.001) for prolonged intubation for each increase in RIFLE class. Independent risk factors for AKI were older age, male gender, previous surgery, preoperative anaemia, length of cardiopulmonary bypass and TV replacement. Importantly, preoperative creatinine and pulmonary artery pressure were not independently associated with AKI. CONCLUSIONS: TV surgery carries a high incidence of postoperative AKI that is associated with adverse outcome. The use of the RIFLE criteria allows comparison with prior studies and is an important predictor of early mortality. The estimation of patient risk for AKI should be based on multivariable prediction.