Kidney injury and mortality after transcatheter aortic valve implantation in a routine clinical cohort.

OBJECTIVES: We aimed at identifying predictors of renal impairment and its impact on long-term outcome after transcatheter aortic valve implantation (TAVI). BACKGROUND: Renal impairment is common in mostly elderly, multimorbid patients undergoing TAVI. The risk of periprocedural renal function impairment and its association with outcome is incompletely understood. METHODS: In 458 consecutive patients (mean age, 80.6 ± 7.0 years, 52.2% women) who underwent routine TAVI procedures, we assessed estimated glomerular filtration rate (eGFR) at baseline, during 72-hr postprocedure and at discharge. Over a median follow-up of 0.96 years, we observed 142 deaths. RESULTS: In multivariable-adjusted models, predictors of renal function deterioration within 72 hr were baseline eGFR (ß = 0.83, 95% confidence interval [CI] = 0.76/0.91; P < 0.0001), body mass index (ß = -1.20, 95% CI = 1.77/-0.62; P < 0.0001), and major access site complications (ß = -14.82, 95% CI = -26.52/-3.11; P = 0.013) including bleeding (ß = -11.97, 95% CI = -21.05/-2.89; P = 0.0099). Strongest renal function predictor of 1-year mortality in risk factor adjusted analyses was the change of eGFR within 72 hr (odds ratio, 0.97; 95% CI = 0.96/0.98; P < 0.0001). The addition of information on the change of eGFR increased the C-statistic of the logistic EuroSCORE (P = 0.021). CONCLUSIONS: In our routine TAVI sample, baseline eGFR, body mass index, and major access site complications mainly owing to bleeding were correlates of acute kidney injury after TAVI. Acute renal impairment was a risk factor for mortality and adverse cardiovascular events which provided risk information beyond the EuroSCORE.

Tissue Doppler imaging identifies myocardial dysfunction in adults with Marfan syndrome.

BACKGROUND: Successful prevention of aortic complications has lead to improved survival of Marfan syndrome (MFS). With increasing age, however, ventricular arrhythmia and heart failure are emerging as life-threatening manifestations of myocardial dysfunction. HYPOTHESIS: We sought to investigate whether echocardiography with tissue Doppler imaging (TDI) identifies myocardial dysfunction in adults with MFS. METHODS: We performed two-dimensional (2-D) and Doppler echocardiography with TDI in 141 individuals with suspected MFS and competent heart valves, including 28 persons with MFS who had not undergone surgery and 86 healthy controls without inherited connective tissue disorders. RESULTS: Demographic profile, 2-D, mitral and pulmonary venous flow indices, and left ventricular ejection fractions were similar in both groups. Conversely, isovolumic relaxation time (p < 0.001) and deceleration time of E velocity (p = 0.005) were longer, and atrial reversal velocities (p = 0.02), and systolic and early diastolic TD velocities were slower in MFS than in controls (p = 0.01). Multiple linear regression analysis excluded association of reduced systolic and early diastolic TD velocities with mitral valve prolapse or other clinical or echocardiographic features of MFS. CONCLUSIONS: Our study identifies reduced systolic and early diastolic TD velocities in adults with MFS. Further studies are mandatory to elucidate whether TD velocities predict arrhythmia and heart failure in MFS.

How to guide stent-graft implantation in type B aortic dissection? Comparison of angiography, transesophageal echocardiography, and intravascular ultrasound.

BACKGROUND: Despite growing interest in stent-graft implantation for type-B aortic dissection, there are no established recommendations to prepare and perform an implantation procedure. METHODS AND RESULTS: We directly compared angiography (ANGIO), transesophageal echocardiography (TEE), and intravascular ultrasound (IVUS) intraprocedually before and after placement of 48 stent grafts in 42 consecutive patients (12 women, 61+/-11 years of age) with acute and chronic type-B aortic dissection for both usefulness and capability to guide aortic stent-graft implantation. Both IVUS and TEE are superior to ANGIO to identify multiple entries (52 and 43 versus 34; P<0.005 each), to diagnose false-lumen slow flow after stent-graft implantation (32 and 31 versus 24; P<0.005 each) and to detect incomplete stent apposition (18 and 16 versus 8; P<0.005 each). In comparison with ANGIO, guide wire position over the entire length of the aorta was documented more frequently by TEE and IVUS (40 and 42 versus 25; P<0.001 each). In 4 patients with abdominal extension of the dissection, only IVUS was able to accurately identify the false lumen over the entire length of the diseased aorta. TEE was superior to IVUS and ANGIO in the detection of endoleaks (5 versus 0 and 1; P<0.05 each). Intraprocedural ANGIO, TEE, and IVUS had been performed without complications in all patients. CONCLUSIONS: TEE in conjunction with ANGIO appears to be advantageous and adds incremental information to safely guide stent-graft placement in type-B aortic dissection. Additional use of IVUS was found to be helpful in patients with complex anatomy and abdominal extension of the dissection.

Intramural hematoma of the aorta: predictors of progression to dissection and rupture.

BACKGROUND: Aortic intramural hematoma (IMH) is a variant of overt aortic dissection. The predictors of progression of IMH to dissection and rupture are still unknown, and strategies for management are not established. METHODS AND RESULTS: A multicenter study was conducted comprising 66 patients with IMH and hospital admission

Predictors of aneurysmal formation after surgical correction of aortic coarctation.

OBJECTIVES: We sought to identify the predictors of aneurysmal formation after surgical correction of aortic coarctation. BACKGROUND: In 9% of patients, aneurysms develop late after corrective surgery of coarctation of the aorta, with a 36% mortality rate if left untreated. However, the predictors of postsurgical aneurysmal formation are unknown. METHODS: Of 25 aortic aneurysms requiring corrective surgery 152 +/- 78 months after the initial coarctation repair, 8 were located in the ascending aorta (type A) and 17 at the site of previous repair (local type). Seventy-four patients without progression of the aortic diameter within 189 +/- 71 months after coarctation repair were used for categorical data analysis in an attempt to identify the predictors of postsurgical aneurysmal formation. RESULTS: Advanced age at coarctation repair (p = 0.004) and patch graft technique (p < 0.0005) independently predicted local aneurysmal formation. Type A aneurysm was univariately associated with the presence of a bicuspid aortic valve (p = 0.02), advanced age at coarctation repair (p = 0.044) and a high preoperative peak systolic pressure gradient of 74 +/- 21 mm Hg (p = 0.041). Conversely, multivariate analysis confirmed only the presence of a bicuspid aortic valve (p = 0.015) as an independent predictor of type A aneurysm. Receiver operating characteristic curve analysis revealed that 72% of patients with a postsurgical aneurysm had an operation at age 13.5 years or more, whereas 69% with no postsurgical aneurysm had an operation at a younger age. CONCLUSIONS: Use of the patch graft technique and late correction of coarctation can predict aneurysmal formation at the site of coarctation repair, although patients with a bicuspid aortic valve may be at risk for an aneurysm developing in the ascending aorta, particularly after late repair of aortic coarctation with high preoperative pressure gradients.

Three-dimensional color Doppler echocardiography for assessing shunt volume in atrial septal defects.

Background Three-dimensional color Doppler echocardiography has been used to assess cardiac blood flow in experimental settings. We tested whether this technique can be applied to assess transatrial shunt flow in patients with atrial septal defect in a clinical setting. Methods In 46 consecutive patients with atrial septal defects, shunt flow was assessed during cardiac catheterization using the Fick method and by conventional 2-D quantitative transesophageal Doppler echocardiography. The averaged values for shunt flow obtained by both methods were used as a reference. Transesophageal 3-D color Doppler echocardiography was performed for analysis of the 3-D flow velocity field of transatrial shunt flow. Shunt volume was calculated by application of the Gauss theorem. Results We found a close correlation between shunt volume (L/min) obtained by either 3-D color Doppler echocardiography or the reference methods ( r = 0.981, P < .001). Using 3-D color Doppler data to predict the reference values, 95% confidence limits were -11.5 to +11.6%. Conclusions Shunt flow in patients with atrial septal defects can be assessed in a clinical setting by transesophageal 3-D color Doppler echocardiography.

Development of a risk score for outcome after transcatheter aortic valve implantation.

AIMS: Transcatheter aortic valve implantation (TAVI) is an increasingly common procedure in elderly and multimorbid patients with aortic stenosis. We aimed at developing a pre-procedural risk evaluation scheme beyond current surgical risk scores. METHODS: We developed a risk algorithm for 1-year mortality in two cohorts consisting of 845 patients undergoing routine TAVI procedures by commercially available devices, mean age 80.9 ± 6.5, 51 % women. Clinical variables were determined at baseline. Multivariable Cox regression related clinical data to mortality (n = 207 deaths). RESULTS: To account for variability related to age and sex and by enrolment site we forced age, sex, and cohort into the score model. Body mass index, estimated glomerular filtration rate, hemoglobin, pulmonary hypertension, mean transvalvular gradient and left ventricular ejection fraction at baseline were most strongly associated with mortality and entered the risk prediction algorithm [C-statistic 0.66, 95 % confidence interval (CI) 0.61-0.70, calibration χ (2)-statistic = 6.51; P = 0.69]. Net reclassification improvement compared to existing surgical risk predication schemes was positive. The score showed reasonable model fit and calibration in external validation in 333 patients, N = 55 deaths (C-statistic 0.60, 95 % CI 0.52-0.68; calibration χ (2)-statistic = 16.2; P = 0.06). Additional measurement of B-type natriuretic peptide and troponin I did not improve the C-statistic. Frailty increased the C-statistic to 0.71, 95 % CI 0.65-0.76. CONCLUSIONS: We present a new risk evaluation tool derived and validated in routine TAVI cohorts that predicts 1-year mortality. Biomarkers only marginally improved risk prediction. Frailty increased the discriminatory ability of the score and needs to be considered. Risk algorithms specific for TAVI may help to guide decision-making when patients are evaluated for TAVI.

Emergency stent-graft placement in thoracic aortic dissection and evolving rupture.

BACKGROUND: Even with rapid diagnosis and effective medical treatment mortality in type B aortic dissection with evidence of extraaortic leakage of blood remains high. Considering a mortality rate of 29% to 50% associated with emergency surgical repair, the concept of endovascular stent-graft placement may become a life-saving option in impending or evolving rupture by endovascular sealing of the entry tear and subsequent abortion of leakage. METHODS: The concept was tested by comparing short-term and 1-year outcomes of 11 patients after emergency endovascular stent-graft placement with historic-matched control patients subjected to conventional therapy. All patients had acute type B dissection complicated by loss of blood into periaortic spaces. RESULTS: Emergency stent-graft placement was successful without periprocedural morbidity, aborted leakage, and ensured reconstruction of the dissected aorta; at a mean follow-up of 15 +/- 6 months no death had occurred in the stent-graft group whereas four patients had died with conventional treatment (p < 0.05). CONCLUSION: With appropriate logistics and expertise, type B aortic dissection with leakage and evolving rupture may benefit from nonsurgical reconstruction of the dissected segment by endovascular stent grafts.

Intentional occlusion of the left subclavian artery during stent-graft implantation in the thoracic aorta: risk and relevance.

PURPOSE: To examine the clinical consequences and/or potential need for postinterventional transposition after stent-graft occlusion of the left subclavian artery (LSA). METHODS: The records of 171 consecutive patients (128 men; mean age 60.2+/-13.2 years, range 20-83) undergoing elective stent-graft repair in the thoracic aorta were reviewed to identify intentional endograft coverage of the ostial LSA, as documented by transesophageal echocardiography and/or aortography. Patients were treated for subacute type B dissection, true aneurysm, pseudoaneurysm, or previously operated type A dissection with persistent false lumen flow in the descending aorta. Among the 171 cases, 22 (12.9%) patients were identified with stent-graft occlusion of the LSA. RESULTS: A systolic blood pressure differential existed between the right (138.4+/-14.0 mmHg) and the left (101.8+/-21.0 mmHg; p<0.05) arms after occlusion of the LSA. No patient showed a malperfusion syndrome during postinterventional hospitalization. During a mean follow-up of 24.0+/-15.8 months, 15 (68.2%) patients remained completely asymptomatic, with no functional deficit or temperature differential between the arms, while 7 patients reported mild symptoms of a subclavian steal syndrome. However, no patient required any secondary surgical intervention. CONCLUSIONS: Stent-graft-induced occlusion of the ostial LSA was tolerated by all patients without chronic functional deficit. In the absence of stenotic vertebral and/or carotid arteries and with a documented intact vertebrobasilar system, prophylactic transposition of the LSA is not required prior to intentional stent-graft occlusion of the LSA.

Angiotensin-converting enzyme insertion/deletion polymorphism does not influence the restenosis rate after coronary stent implantation.

BACKGROUND: Experimental studies have shown an activation of the angiotensin-converting enzyme (ACE) system as a response to endothelial injury. Recent publications have elucidated the hypothesis that the ACE gene polymorphism may influence the level of late luminal loss after coronary stent implantation. It is still unclear whether the polymorphism of the angiotensin gene is a major predictor of the extent of neointimal hyperplasia. In this multicenter study, we therefore tested the relationship between the ACE gene polymorphism and the restenosis rate after coronary stent implantation. METHODS: As a substudy of the optimization with intracoronary ultrasound (ICUS) to reduce stent restenosis (OPTICUS) study, we analyzed ACE serum levels and the ACE gene polymorphism in 154 patients at 9 different centers. All patients underwent elective coronary stent implantation in a stenosis of a major coronary vessel. Balloon inflations were repeated until a satisfactory result was achieved in on-line quantitative coronary angiography or ICUS fulfilling the OPTICUS study criteria. After follow-up of 6 months, all patients underwent reangiography under identical projections as the baseline procedure. A blinded quantitative analysis of the initial procedure as well as the follow-up examinations were performed by an independent core laboratory. ACE gene polymorphism and ACE serum activity were measured at the 6-month follow-up in a double-blinded setting. RESULTS: With respect to the ACE gene polymorphism, there were three subgroups: DD genotype (48 patients), ID (83 patients) and II (23 patients). The subgroups did not differ in regard to age, gender, extent of coronary artery disease, stenosis length, initial degree of stenosis or degree of stenosis after stent implantation. In all, 39 patients (25.3%) had significant restenosis: 12 DD patients (25.0%), 18 ID patients (21.7%) and 9 II patients (39.1%) (odds ratio 2.164, 95% confidence interval 0.853-5.493). We obtained the following results for ACE serum levels: 0.53 micromol/l/s in the DD subgroup, 0.29 micromol/l/s in the ID subgroup and 0.09 micromol/l/s in the II subgroup (p < 0.001). Multivariate logistic regression analysis of the influence of ACE gene polymorphism on the restenosis rate after coronary stent implantation adjusted for lesion length (>12 mm), ACE inhibitor or hydroxymethylglutaryl coenzyme A reductase (CSE) inhibitor treatment, age, male gender, diabetes mellitus, hypertension, high cholesterol, family history, smoking and three-vessel disease did not uncover any statistic significance. CONCLUSIONS: In contrast to other study groups, we were unable to disclose that the DD polymorphism of the ACE gene was associated with a higher rate of restenosis after coronary stent implantation in this multicenter study. In addition, patients with higher ACE serum levels did not show a higher restenosis rate in this trial. We conclude that the pathogenesis of restenosis is a multifactorial process involving various genetic and nongenetic factors.

Value of intravascular ultrasound for endovascular stent-graft placement in aortic dissection and aneurysm.

BACKGROUND: Endovascular stent-graft placement is a new concept for the treatment of aortic dissection and aneurysm. Intravascular ultrasound (IVUS) with established diagnostic features may be instrumental in guiding endovascular procedures. METHODS: We performed IVUS and digital angiography before, during, and after implantation of 47 stent grafts in 40 patients with Stanford type B dissection (26 patients, 28 stent grafts), thoracic aneurysm (9 patients, 11 stent grafts), and abdominal aneurysm (5 patients, 8 stent grafts). RESULTS: IVUS could clearly identify the aortic anatomy and differentiate between true and false lumen in all cases of dissection. In four patients with type B dissection extending from the thoracic to the abdominal aorta the true lumen was exclusively identified by IVUS, and thus, essential for safe execution of the procedure. In another patient stent-graft placement in the aorta was optimized by covering a second entry detected by IVUS, but undetected by angiography. The site of stent implantation, the true and false lumen, as well as entry and reentry were always identified in both thoracic and abdominal aorta. In comparison with angiography, IVUS information led to additional balloon molding due to incomplete stent apposition in seven cases. CONCLUSIONS: As an adjunctive imaging modality IVUS is likely to improve stent-graft placement in aortic type B dissection, especially in patients with abdominal extension.