Accelerated Progression and Morbidity in Patients With Aortic Stenosis on Chronic Dialysis

Minimum-incision transsubclavian transcatheter aortic valve replacement with balloon-expandable valve for dialysis patients

BACKGROUND

Dialysis patients undergoing transcatheter aortic valve replacement (TAVR) face increased risk and have poorer outcomes than non-dialysis patients. Moreover, TAVR in dialysis patients using an alternative approach is considered extremely risky and little is known about the outcomes. We routinely perform minimum-incision transsubclavian TAVR (MITS-TAVR), which is contraindicated for transfemoral (TF) TAVR. This study aimed to evaluate the outcomes of MITS-TAVR compared with those of TF-TAVR in dialysis patients.

METHODS

This single-center, observational study included 79 consecutive dialysis patients who underwent MITS-TAVR (MITS group, n = 22) or TF-TAVR (TF group, n = 57) under regional anesthesia.

RESULTS

The rates of peripheral artery disease (MITS vs. TF, 72.7 % vs. 26.3 %; p < 0.01), shaggy aortas (MITS vs. TF, 63.6 % vs. 5.26 %; p < 0.01), and tortuous aortas (MITS vs. TF, 13.6 % vs. 1.75 %; p = 0.031) were significantly higher in the MITS group. The 30-day mortality was 2.53 % and comparable between the two groups (MITS vs. TF, 4.54 % vs. 1.75 %; p = 0.479). In the MITS group, 14 patients had ipsilateral dialysis fistulas, and three patients had patent in situ ipsilateral internal thoracic artery grafts; however, no vascular complications were observed. Kaplan-Meier survival curves for the two groups showed no significant difference in the survival rate (at 2 years; MITS vs. TF, 77.3 % vs. 68.8 %; p = 0.840) and freedom from cardiovascular mortality (at 2 years; MITS vs. TF, 90.9 % vs. 96.5 %; p = 0.898). The multivariable Cox proportional hazard model also indicated that survival in the MITS group was not significantly different from that in the TF group (hazard ratio 1.48; 95 % confidence interval, 0.77-2.85, p = 0.244). The patency rate of ipsilateral dialysis fistula was 100 % during follow-up.

CONCLUSION

The outcome of MITS-TAVR was comparable to that of TF-TAVR in dialysis patients, despite the higher risk of patient characteristics.

Early structural valve deterioration of balloon expandable transcatheter aortic valve leaflets due to intrinsic and extrinsic nodular calcifications in a haemodialysis patient: a case report

Background

Several reports have shown that transcatheter aortic valves are comparable in durability to surgical aortic valves. However, early structural valve deterioration (SVD) is rarely reported to occur, especially in haemodialysis patients.

Case summary

We present a case of rapidly progressive bioprosthetic aortic valve stenosis in a patient with end-stage renal disease secondary to diabetic nephropathy in an 83-year-old female admitted due to progressive dyspnoea and orthopnoea. A 23 mm sized SAPIEN3 bioprosthetic aortic valve showed normal function for the first year after transcatheter aortic valve implantation (TAVI), but then rapidly developed stenosis and required acute hospitalization for heart failure a year and a half after surgery. Emergent surgical aortic valve replacement with a 19 mm On-X valve (CryoLife, Kennesaw, GA, USA) was performed. Pathological examination of the explanted SAPIEN 3 valve demonstrated severely degenerated bioprosthetic pericardial leaflets with severe intrinsic and extrinsic nodular calcifications, which could limit the leaflet motion.

Discussion

There is a lack of reports on the long-term procedural outcomes of TAVI in haemodialysis patients. The development of SVD in patients undergoing dialysis is multifactorial and has yet to be fully elucidated. In the presented case, the removed TAVI valve had severe extrinsic calcified nodules alongside a fibrin thrombus. Considering these pathological findings, antithrombotic therapy to prevent fibrin thrombus from adhering to the TAVI valve may be important to avoid early SVD.

Mechanical vs Bioprosthetic Aortic Valve Replacement in Patients on Dialysis: Long-term Outcomes

BACKGROUND

Using the Japan National Clinical Database and additional data, this study is an analysis of long-term survival of dialysis-dependent patients who underwent aortic valve replacement (AVR).

METHODS

Dialysis-dependent patients who underwent de novo AVR between 2010 and 2012 and who were registered in the database were included. Concomitant aortic surgery and transcatheter aortic valve replacement were excluded. Additional data on the underlying kidney disease, the duration of dialysis, and clinical outcomes were registered between October 29, 2019, and August 30, 2020. The primary outcome was all-cause mortality. The secondary outcomes were cerebral infarction, cerebral bleeding, gastrointestinal bleeding, and prosthetic valve failure.

RESULTS

After propensity score matching, 1016 cases (508 each in the bioprosthetic and mechanical valve groups) were matched. The median follow-up period was 3.29 years (interquartile range [IQR], 0.59 years, 6.25 years). The median survival time was 5.38 years (IQR, 1.20 and 9.26 years) in the mechanical valve group and 4.98 years (IQR, 1.69 and 9.62 years) in the bioprosthetic valve group. The Cox regression model showed no significant difference in long-term survival between the groups (mechanical valve: hazard ratio [HR], 0.895; 95% CI, 0.719-1.113; P = .318). The incidences of cerebral infarction and prosthetic valve failure requiring admission were similar between the groups. Cerebral bleeding (HR, 2.143; 95% CI, 1.125-4.080; P = .002) and gastrointestinal bleeding (HR, 2.071; 95% CI, 1.243-3.451; P = .0005) were more frequent in the mechanical valve group.

CONCLUSIONS

Long-term survival of dialysis-dependent patients was similar regardless of whether mechanical valves or bioprosthetic valves were implanted. The incidences of cerebral and gastrointestinal bleeding were 2-fold higher in the mechanical valve group.

Trend, predictors and outcomes of transcatheter aortic valve implantation in patients with end-stage renal disease: Insights from the nationwide readmissions database

BACKGROUND

Transcatheter aortic valve implantation (TAVI) is the standard of care for patients with severe aortic valve stenosis (AS). However, evidence on its safety in patients with end-stage renal disease (ESRD) is limited.

METHODS

The Nationwide Readmissions Database (NRD) from 2015 to 2019 was queried to identify patients undergoing TAVI in ESRD versus patients with no ESRD. The in-hospital, 30-day and 180-day outcomes were assessed using a propensity-score matched (PSM) analysis to calculate adjusted odds ratios (aOR).

RESULTS

A total of 198,816 underwent TAVI, of which 34,546 patients (TAVI-ESRD 16,986 vs. non-ESRD 17,560) were selected using PSM analysis. The adjusted odds of net adverse cardiovascular events (NACE) (aOR 1.65, 95 % CI 1.49-1.82), in-hospital mortality (aOR 2.99, 95 % CI 2.52-3.55), major bleeding (aOR 1.21, 95 % CI 1.05-1.40), postprocedural cardiogenic shock (aOR 1.54, 95 % CI 1.11-2.13), and need for permanent pacemaker implantation (PPM) (aOR 1.24, 95 % CI 1.15-1.38) were significantly higher in TAVI-ESRD patients compared with non-ESRD patients at index admission. There was no significant difference in the odds of stroke (aOR 1.09, 95 % CI 0.86-1.34) and cardiac tamponade (aOR 1.06, 95 % CI 0.78-1.45) between the two groups. At 30- and 180-day follow-up, the odds of readmission, NACE, and mortality remained high in TAVI-ESRD patients.

CONCLUSION

ESRD patients undergoing TAVI have a high risk of NACE, in-hospital mortality, and major bleeding compared with patients with no ESRD.

End-stage renal disease, calcification patterns and clinical outcomes after TAVI

BACKGROUND

Patients with chronic hemodialysis due to end-stage renal disease (ESRD) or severely impaired kidney function (CKD) constitute a relevant share of patients undergoing trans-catheter aortic valve implantation (TAVI). However, data on specific challenges and outcomes remain limited.

AIM

We aimed to characterize this patient population, evaluate clinical results and assess the significance of calcification patterns.

METHODS

This retrospective single-center analysis evaluated 2,712 TAVI procedures (2012-2019) according to baseline renal function: GFR < 30 ml/min/1.73m2 (CKD; n = 210), chronic hemodialysis (ESRD; n = 119) and control (CTRL; n = 2383). Valvular and vascular calcification patterns were assessed from contrast-enhanced multi-detector computed tomography. Outcomes were evaluated in accordance with the VARC-2 definitions.

RESULTS

Operative risk was higher in ESRD and CKD vs. CTRL (STS-score 8.4% and 7.6% vs. 3.9%, p < 0.001) and patients with ESRD had more severe vascular calcifications (49.1% vs. 33.9% and 29.0%, p < 0.01). Immediate procedural results were similar but non-procedure-related major/life-threatening bleeding was higher in ESRD and CKD (5.0% and 5.3% vs. 1.6%, p < 0.01). 3-year survival was impaired in patients with ESRD and CKD (33.3% and 35.3% vs. 65.4%, p < 0.001). Multivariable analysis identified ESRD (HR 1.60), CKD (HR 1.79) and vascular calcifications (HR 1.29) as predictors for 3-year and vascular calcifications (HR 1.51) for 30-day mortality.

CONCLUSION

Patients with ESRD and CKD constitute a vulnerable patient group with extensive vascular calcifications. Immediate procedural results were largely unaffected by renal impairment, yielding TAVI a particularly valuable treatment option in these high-risk operative patients. Mid-term survival was determined by underlying renal disease, cardiovascular comorbidities, and vascular calcifications as a novel risk marker.

Readmission rates and risk factors for readmission after transcatheter aortic valve replacement in patients with end-stage renal disease

Objectives

We sought to examine readmission rates and predictors of hospital readmission following TAVR in patients with ESRD.

Background

End-stage renal disease (ESRD) is associated with poor outcomes following transcatheter aortic valve replacement (TAVR).

Methods

We assessed index hospitalizations for TAVR from the National Readmissions Database from 2017 to 2018 and used propensity scores to match those with and without ESRD. We compared 90-day readmission for any cause or cardiovascular cause. Length of stay (LOS), mortality, and cost were assessed for index hospitalizations and 90-day readmissions. Multivariable logistic regression was performed to identify predictors of 90-day readmission.

Results

We identified 49,172 index hospitalizations for TAVR, including 1,219 patients with ESRD (2.5%). Patient with ESRD had higher rates of all-cause readmission (34.4% vs. 19.2%, HR 1.96, 95% CI 1.68–2.30, p<0.001) and cardiovascular readmission (13.2% vs. 7.7%, HR 1.85, 95% CI 1.44–2.38, p<0.001) at 90 days. During index hospitalization, patients with ESRD had longer length of stay (mean difference 1.9 days), increased hospital cost (mean difference $42,915), and increased in-hospital mortality (2.6% vs. 0.9%). Among those readmitted within 90 days, patients with ESRD had longer LOS and increased hospital charge, but similar in-hospital mortality. Diabetes (OR 1.86, 95% CI 1.31–2.64) and chronic pulmonary disease (OR 1.51, 95% CI 1.04–2.18) were independently associated with higher odds of 90-day readmission in patients with ESRD.

Conclusion

Patients with ESRD undergoing TAVR have higher mortality and increased cost associated with their index hospitalization and are at increased risk of readmission within 90 days following TAVR.

Factors associated with aortic valve stenosis in Japanese patients with end-stage kidney disease

Background

Aortic valve stenosis (AS) has a high prevalence and poor prognosis in patients who receive maintenance dialysis. However, few large-scale observational studies in Japan have investigated patients with AS who underwent dialysis. In this study, we investigated the prevalence and factors associated with AS in Japanese patients who underwent dialysis.

Methods

In this cross-sectional analysis, we enrolled patients who underwent dialysis and transthoracic echocardiography between July 1, 2017 and June 30, 2018. Patients with a maximum aortic jet velocity (Vmax) ≥ 2.0 m/s, pressure gradient (PG) between the left ventricle and ascending aorta (mean PG) ≥ 20 mmHg, or aortic valve area (AVA) ≤ 1.0 cm² were categorized into the AS group (G1). Patients with Vmax ≥ 3.0 m/s, mean PG ≥ 20 mmHg, or AVA ≤ 1.0 cm² were categorized into the moderate and severe AS groups (G2). We performed multivariate logistic regression analysis and compared G1 and G2 with the non-AS group to determine the risk factors for AS. We also investigated the risk factors for aortic valve calcification, which is a pre-stage for AS.

Results

Of the 2,786 patients investigated, 555 (20.0%) and 193 (6.9%) were categorized into G1 and G2, respectively. Multivariate logistic regression analysis revealed that age, long-term dialysis, and elevated serum phosphorus levels were associated with AS in both the groups (p < 0.05). These factors were converted into ordinal categories, and a multivariate logistic regression analysis was performed. Patients with serum phosphorus levels measuring 5.0–5.9 mg/dL and > 6.0 mg/dL showed a higher risk of AS than those with serum phosphorus levels measuring < 4.0 mg/dL (odds ratio 2.24, p = 0.01 and odds ratio 2.66, p = 0.005, respectively). Aortic valve calcification was associated with age, long-term dialysis, diabetes mellitus, administration of vitamin D receptor activators, elevated serum calcium levels, and anemia (p < 0.05 for all).

Conclusions

Patients on dialysis showed a high prevalence of AS, which was associated with age, long-term dialysis, and elevated serum phosphorus levels.

Trial registration

UMIN000026756, registered on March 29, 2017.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-022-02758-y.

Towards Personalized Therapy of Aortic Stenosis

Calcific aortic stenosis (CAS) is the most common cause of acquired valvular heart disease in adults with no available pharmacological treatment to inhibit the disease progression to date. This review provides an up-to-date overview of current knowledge of molecular mechanisms underlying CAS pathobiology and the related treatment pathways. Particular attention is paid to current randomized trials investigating medical treatment of CAS, including strategies based on lipid-lowering and antihypertensive therapies, phosphate and calcium metabolism, and novel therapeutic targets such as valvular oxidative stress, coagulation proteins, matrix metalloproteinases, and accumulation of advanced glycation end products.

Strict control of phosphorus concentration of hemodialysis patients may decrease structural valve deterioration after aortic valve replacement

OBJECTIVES

The number of hemodialysis patients requiring aortic valve replacement (AVR) is increasing. Although bioprosthetic valves are increasingly popular, they are associated with a risk of structural valve deterioration (SVD). The aim of this study is to examine the outcomes of bioprosthetic valves in hemodialysis patients undergoing AVR and to identify treatment strategies that can decrease the risk of SVD.

METHODS

Between February 2010 and November 2019, 61 patients on hemodialysis underwent AVR using bioprosthetic valves at our hospital. Five patients died while still in the hospital. Kaplan-Meier estimates of overall survival and univariate Cox proportional hazards regression analyses were performed for the remaining 56 patients.

RESULTS

During follow-up, there were six SVD events (10.7%) related to the bioprosthetic valves. The survival rate was 67.9% at 3 years and 39.5% at 5 years. In all SVD cases, SVD was caused by aortic stenosis. The mean interval between AVR and the discovery of SVD was 41.5 months. The SVD-free rate was 88.6% at 3 years and 65.3% at 5 years. Preoperative phosphorus levels are associated with SVD risk. High preoperative phosphorus concentration is associated with elevated SVD risk.

CONCLUSIONS

In this study, we determined that the risk of SVD can be influenced by preoperative phosphorus level. Strict control of the phosphorus concentration of hemodialysis patients may decrease structural valve deterioration after aortic valve replacement.

Association between Serum Phosphate Levels and the Development of Aortic Stenosis in Patients Undergoing Hemodialysis

We aimed to investigate the factors associated with the development of aortic stenosis (AS) in patients undergoing hemodialysis (HD), and to elucidate the prognosis of HD patients with AS. Patients on HD that had also undergone echocardiography at Nagasaki Renal Center between July 2011 and June 2012 were included. Patients with AS at the time of inclusion were excluded. The diagnosis of AS was based on an annual routine or additional echocardiography. The patients were followed up until June 2021. The association between patient background and AS was also evaluated. Of the 302 patients (mean age, 67.4 ± 13.3 years; male, 58%; median dialysis history, 4.7 years), 60 developed AS and 10 underwent aortic valve replacement. A Cox proportional hazards model revealed that age (hazard ratio (HR), 1.07; 95% confidential interval (CI), 1.04–1.10; p < 0.001) and serum phosphate levels (HR, 1.40; 95%CI, 1.16–1.67, p < 0.001) were independent risk factors for developing AS. Incidentally, there was no significant mortality difference between patients with AS and those without (p = 0.53). Serum phosphate levels are a risk factor for developing AS and should be controlled. Annual echocardiography may contribute to the early detection of AS and improves the prognosis of patients undergoing HD.

Impact of dialysis in patients undergoing bioprosthetic aortic valve replacement

OBJECTIVES

To determine the incidence of bioprosthetic structural valve deterioration in dialysis patients undergoing aortic valve replacement compared to that in patients without dialysis.

METHODS

This single-centre retrospective observational study included 1159 patients who underwent aortic valve replacement using bioprosthetic valves for aortic stenosis and/or regurgitation at our institution between 2007 and 2017 [patients with dialysis (group D, n = 134, 12%) or without dialysis (group N, n = 1025, 88%)]. To adjust for potential differences between groups in terms of initial preoperative characteristics or selection bias, a propensity score analysis was conducted. The final sample that was used in the comparison included 258 patients, as follows: 129 patients with dialysis (group D) and 129 patients without dialysis (group N). The cumulative incidences of all-cause death, cardiac death and moderate or severe structural valve deterioration were estimated using the Kaplan-Meier method.

RESULTS

Operative mortality was significantly higher in group D than group N (9% vs 0%, P = 0.001). Kaplan-Meier analysis revealed that in group D, the incidence was significantly higher for all-cause death (P < 0.001, 50% vs 18% at 5 years), cardiac death (P = 0.001, 18% vs 5% at 5 years) and moderate or severe structural valve deterioration (P < 0.001, 29% vs 5% at 5 years) compared with group N.

CONCLUSIONS

The incidence of structural valve deterioration in dialysis patients undergoing aortic valve replacement was higher than that in patients without dialysis. Bioprosthetic valves should be carefully selected in dialysis patients undergoing aortic valve replacement.

Evaluation and Management of Aortic Stenosis in Chronic Kidney Disease: A Scientific Statement From the American Heart Association

Aortic stenosis with concomitant chronic kidney disease (CKD) represents a clinical challenge. Aortic stenosis is more prevalent and progresses more rapidly and unpredictably in CKD, and the presence of CKD is associated with worse short-term and long-term outcomes after aortic valve replacement. Because patients with advanced CKD and end-stage kidney disease have been excluded from randomized trials, clinicians need to make complex management decisions in this population that are based on retrospective and observational evidence. This statement summarizes the epidemiological and pathophysiological characteristics of aortic stenosis in the context of CKD, evaluates the nuances and prognostic information provided by noninvasive cardiovascular imaging with echocardiography and advanced imaging techniques, and outlines the special risks in this population. Furthermore, this statement provides a critical review of the existing literature pertaining to clinical outcomes of surgical versus transcatheter aortic valve replacement in this high-risk population to help guide clinical decision making in the choice of aortic valve replacement and specific prosthesis. Finally, this statement provides an approach to the perioperative management of these patients, with special attention to a multidisciplinary heart-kidney collaborative team-based approach.

Trends of utilization and outcomes after transcatheter and surgical aortic valve replacement on chronic dialysis

BACKGROUND AND AIM

Trends of utilization and outcomes of transcatheter aortic valve replacement (TAVR) and surgical aortic valve replacement (SAVR) for patients on chronic dialysis (CD) are not well described. We aimed to assess the trends in utilization and outcomes of TAVR and SAVR on CD.

METHODS

Nationwide Readmission Databases from 2013 to 2017 was analyzed. International Classification of Diseases Clinical Modification 9 and 10 codes were used to identify diagnoses and procedures. A multivariable regression model was used to compare the outcomes expressed as adjusted odds ratio (aOR) and 95% confidence interval (CI).

RESULTS

A total of 5731 TAVR and 6491 SAVR were performed in patients with CD, respectively. The volume of TAVR increased by approximately four-folds and SAVR increased by approximately 33%. However, amongst patients with CD, the percentage of TAVR increased, whereas that of SAVR decreased (p < .001 for all). In 2016 and 2017, TAVR volume surpassed that of SAVR on CD. In-hospital mortality remained similar in TAVR (aOR: 0.92; 95% CI: 0.79-1.07; p-trend = .23) whereas it increased significantly in SAVR (aOR: 1.14: 95% CI: 1.05-1.25, p-trend = .002). In 2017, in-hospital mortality and 30-day readmission were significantly higher in TAVR among CD than non-CD patients.

CONCLUSION

Despite increased use of TAVR among CD, there still is an opportunity for improvement in outcome of aortic valve replacement for those on CD.

Severe Aortic Stenosis and Chronic Kidney Disease: Outcomes and Impact of Aortic Valve Replacement

Background

The prognostic significance of chronic kidney disease (CKD) in severe aortic stenosis is poorly understood and no studies have yet evaluated the effect of aortic‐valve replacement (AVR) versus conservative management on long‐term mortality by stage of CKD.

Methods and Results

We included 4119 patients with severe aortic stenosis. The population was divided into 4 groups according to the baseline estimated glomerular filtration rate: no CKD, mild CKD, moderate CKD, and severe CKD. The 5‐year survival rate was 71±1% for patients without CKD, 62±2% for those with mild CKD, 54±3% for those with moderate CKD, and 34±4% for those with severe CKD (P<0.001). By multivariable analysis, patients with moderate or severe CKD had a significantly higher risk of all‐cause (hazard ratio [HR] [95% CI]=1.36 [1.08–1.71]; P=0.009 and HR [95% CI]=2.16 [1.67–2.79]; P<0.001, respectively) and cardiovascular mortality (HR [95% CI]=1.39 [1.03–1.88]; P=0.031 and HR [95% CI]=1.69 [1.18–2.41]; P=0.004, respectively) than patients without CKD. Despite more symptoms, AVR was less frequent in moderate (P=0.002) and severe CKD (P<0.001). AVR was associated with a marked reduction in all‐cause and cardiovascular mortality versus conservative management for each CKD group (all P<0.001). The joint‐test showed no interaction between AVR and CKD stages (P=0.676) indicating a nondifferentialeffect of AVR across stages of CKD. After propensity matching, AVR was still associated with substantially better survival for each CKD stage relative to conservative management (all P<0.0017).

Conclusions

In severe aortic stenosis, moderate and severe CKD are associated with increased mortality and decreased referral to AVR. AVR markedly reduces all‐cause and cardiovascular mortality, regardless of the CKD stage. Therefore, CKD should not discourage physicians from considering AVR.

Aortic stenosis in patients with kidney failure: Is there an advantage for a PD-first policy?

Aortic stenosis (AS) is the most common valvular disease. It is twice as prevalent in patients with kidney failure as compared to the general population. In addition, AS progresses at a faster rate and is associated with a higher risk of death and poorer quality of life in patients on dialysis. Chronic kidney disease–mineral and bone disorder (CKD-MBD), inflammation, and hemodynamic disturbances contribute to the pathophysiology and progression of AS. Whether the type of dialysis modality, that is, hemodialysis (HD) versus peritoneal dialysis (PD), has a differential impact on the development and progression of AS in patients with kidney failure remains debated. Recent data indicate that the prevalence of valvular calcifications might be lower and the development of AS delayed in PD patients, as compared to those treated with HD. This could be accounted for by several mechanisms including reduced valvular shear stress, better preservation of residual kidney function (with better removal of protein-bound uremic toxins and CKD-MBD profile), and lower levels of systemic inflammation. Given the high morbidity and mortality rates related to interventional procedures in the population with kidney failure, surgical and transcatheter aortic valve replacement should be considered in selected patients with severe AS. Strategies slowing down the progression of aortic valve remodeling should remain the cornerstone in the management of individuals with kidney failure and mild to moderate AS. This review explores the potential benefits of PD in patients with kidney failure and AS and provides some clues to help clinicians in the decision-making process when options for kidney replacement therapy are considered in patients with AS.

Trans-Catheter Aortic Valve Replacement and Surgical Aortic Valve Replacement Outcomes in Patients with Dialysis: Systematic Review and Meta-Analysis

BACKGROUND

Dialysis is associated with higher rate of aortic valve calcification and higher cardiovascular mortality. Transcatheter aortic valve replacement (TAVR) is an established alternative for surgical aortic valve replacement (SAVR) in patients with higher and intermediate co-morbidities including dialysis.

METHODS

Two independent investigators systematically searched Medline, Cochrane, and Web of Science. The ROBINS-I tool was used to analyze and assess the bias from the selected studies.

RESULTS

The search resulted in 4 observational studies with a total of 966 patients. TAVR in dialysis patients was associated with no significant difference in in-hospital mortality [8.1% vs 10.3%; OR (95% CI) 0.74 (0.35, 1.60), I2 = 50%, P = 0.45], risk-of-strokes at 30 days [2% vs 4.4%; OR (95% CI) 0.49 (0.22, 1.09), I2 = 0%, P = 0.08], vascular complications [12.7% vs 13.2%; OR (95% CI) 0.96 (0.55, 1.67), I2 = 0%, P = 0.89], need of blood transfusion [43.1% vs 66.4%; OR (95% CI) 0.27 (0.05, 1.39), I2 = 89%, P = 0.12], or bleeding risk [5.6% vs 6.8%; OR (95% CI) 0.91 (0.18, 4.64), I2 = 5%, P = 0.91] when compared to SAVR. TAVR was associated with significantly shorter length of stay [8.5 days vs 14.2 days; mean difference (95% CI) -5.89 (-9.13, -2.64), I2 = 76%, P < 0.0001] and higher pacemaker implantation [11.4% vs 6.8%; OR (95% CI) 1.74 (1.07, 2.81), I2 = 5%, P = 0.02].

CONCLUSION

TAVR outcomes were comparable to SAVR but had a significantly shorter length of stay and a higher pacemaker implantation rate in dialysis patients.

Echocardiographic assessment of cardiac structure and function in chronic renal disease

Chronic kidney disease (CKD) is a global health problem and is independently associated with increased risk for cardiovascular disease (CVD). The presence and severity of CKD is strongly related to the progression of coronary atherosclerosis, ventricular hypertrophy, myocardial fibrosis, valvular calcification, and cardiac conduction system abnormalities. Echocardiography plays a major role in the assessment of structural and functional cardiac abnormalities in CKD including abnormal left-ventricular (LV) geometry, LV diastolic dysfunction, valvular disease, and left atrial dilatation, which are very frequently present especially in patients with end-stage renal disease.

Proteinuria is an independent predictor of rapid progression of mild to moderate aortic stenosis in patients with preserved renal function

Although proteinuria is a well-known risk factor for cardiovascular disease, its relationship with the progression of aortic stenosis (AS) has not been established. Our aim was to investigate the relationship between proteinuria (detected by urine dipstick test) and AS progression (assessed by the annualized reduction rate of aortic valve area [AVA]). A total of 460 patients with mild to moderate AS (defined by a peak velocity of 2.0-4.0 m/s) without end-stage renal disease who underwent two echocardiograms at least 3 months apart were included. The progression of AS was significantly faster in patients with proteinuria than those without (108 patients vs. 352 patients; annualized reduction rate of AVA, - 7.7 ± 13.5% vs. - 4.5 ± 11.6%; p = 0.017). The relationship between the presence of proteinuria and the accelerated progression of AS was significant among patients with estimated glomerular filtration rate (eGFR) ≥ 60 mL/min/1.73 m² (- 11.0 ± 17.5% vs. - 4.2 ± 10.0%; p < 0.001), but not among those with eGFR 15-60 mL/min/1.73 m² (- 5.8 ± 10.3 vs. - 5.3 ± 14.8%; p = 0.822). When stratified by the presence of diabetes, the association of proteinuria with AS progression was only significant in patients without diabetes (- 8.1 ± 12.0% vs. - 8.1 ± 15.7%; p = 0.018). Multivariable logistic regression analysis identified that the presence of proteinuria was an independent predictor of AS progression. The progression of AS was accelerated in patients with mild to moderate AS and proteinuria, particularly among those with preserved renal function and no diabetes.

Acute Heart Failure in Patients With Severe Aortic Stenosis - Insights From the CURRENT AS Registry

BACKGROUND

Clinical profiles of acute heart failure (AHF) complicating severe aortic stenosis (AS) remain unclear.

METHODS AND RESULTS

From a Japanese multicenter registry enrolling consecutive patients with severe AS, 3,813 patients were categorized into the 3 groups according to the symptom of heart failure (HF); No HF (n=2,210), chronic HF (CHF) (n=813) and AHF defined as hospitalized HF at enrolment (n=790). Median follow-up was 1,123 days with 93% follow-up rate at 2 years. Risk factors for developing AHF included age, female sex, lower body mass index, untreated coronary artery stenosis, anemia, history of HF, left ventricular ejection fraction <50%, presence of any combined valvular disease, peak aortic jet velocity ≥5 m/s and tricuspid regurgitation pressure gradient ≥40 mmHg, and negative risk factors included dyslipidemia, history of percutaneous coronary intervention and hemodialysis. Respective cumulative 5-year incidences of all-cause death and HF hospitalization in No HF, CHF and AHF groups were 37.1%, 41.8% and 61.8% (P<0.001) and 20.7%, 33.8% and 52.3% (P<0.001). Even in the initial aortic valve replacement (AVR) stratum, AHF was associated with excess 5-year mortality risk relative to No HF and CHF (adjusted hazard ratio [HR] 1.64; 95% confidence interval [CI]: 1.14-2.36, P=0.008; adjusted HR 1.47; 95% CI: 1.03-2.11, P=0.03, respectively).

CONCLUSIONS

AHF complicating severe AS was associated with an extremely dismal prognosis, which could not be fully resolved by AVR. Careful management to avoid the development of AHF is crucial.

Impact of aortic plaque on progression rate and prognosis of aortic stenosis

BACKGROUNDS

Patients with aortic stenosis (AS) have a high prevalence of aortic plaque. However, no data exist regarding the clinical significance and prognostic value of aortic plaque in AS patients. This study examines the impact of aortic plaque on the rate of progression and clinical outcomes of AS.

METHODS

We retrospectively investigated 1812 transesophageal echocardiographic examinations between 2008 and 2015. We selected 100 consecutive patients (mean age; 75.1±7.4years) who showed maximal aortic jet velocity (AV-Vel) ≥2.0m/s by transthoracic echocardiography (TTE) and received follow-up TTE (mean follow-up duration 25±17months), and the mean progression rate of AV-Vel was calculated. Clinical and echocardiographic characteristics, including severity of aortic plaque, and cardiac events were examined.

RESULTS

At initial TTE, mean AV-Vel was 3.68±0.94m/s and mean aortic valve area 0.98±0.32cm². Mean progression rate of AV-Vel was 0.41m/s/year in 38 patients with severe aortic plaque, and -0.03m/s/year in the remaining 62 patients without severe aortic plaque. Severe aortic plaque (odds ratio[OR], 8.32) and hemodialysis (OR, 6.03) were independent predictors of rapid progression. The event-free survival rate at 3years was significantly lower in patients with severe aortic plaque than in those without (52% vs 82%, p=0.002). Severe aortic plaque (hazard ratio[HR], 2.89) and AV-Vel at initial TTE (HR, 3.28) were identified as independent predictors of cardiac events.

CONCLUSION

Severe aortic plaque was a predictor of rapid progression and poor prognosis in AS patients. Evaluation of aortic plaque provides additional information regarding surgical scheduling and follow-up.

Outcomes of Transcatheter and Surgical Aortic Valve Replacement in Patients on Maintenance Dialysis

BACKGROUND

The introduction of transcatheter aortic valve replacement (TAVR) expanded definitive therapy of aortic stenosis to many high-risk patients, but it has not been fully evaluated in the dialysis population. We aimed to evaluate the current trend and in-hospital outcome of surgical aortic valve replacement (SAVR) and TAVR in the dialysis population.

METHODS

Severe aortic stenosis patients on maintenance dialysis who underwent SAVR or TAVR in the Nationwide Inpatient Sample database from January 1, 2005, through December 31, 2014, were included in our comparative analysis. The trends of SAVR and TAVR were assessed. In-hospital mortality, rates of major adverse events, hospital length of stay, cost of care, and intermediate care facility utilization were compared between the 2 groups using both unadjusted and propensity-matched data.

RESULTS

Utilization of aortic valve replacement in dialysis patients increased 3-fold; a total of 2531 dialysis patients who underwent either SAVR (n = 2264) or TAVR (n = 267) between 2005 and 2014 were identified. Propensity score matching yielded 197 matched pairs. After matching, a 2-fold increase in in-hospital mortality was found with SAVR compared with TAVR (13.7% vs 6.1%, P = .021). Patients who underwent TAVR had more permanent pacemaker implantation (13.2% vs 5.6%, P = .012) but less blood transfusion (43.7% vs 56.8%, P = .02). Rates of other key morbidities were similar. Hospital length of stay (19 ± 16 vs 11 ± 11 days, P <.001) and non-home discharges (44.7% vs 31.5%, P = .002) were significantly higher with SAVR. Cost of hospitalization was 25% less with TAVR.

CONCLUSION

In patients on maintenance dialysis, TAVR is associated with lower hospital mortality, resource utilization, and cost in comparison with SAVR.

Severe Aortic Stenosis in Dialysis Patients

BACKGROUND

Characteristics and prognosis of hemodialysis patients with severe aortic stenosis have not yet been well defined.

METHODS AND RESULTS

The CURRENT AS (contemporary outcomes after surgery and medical treatment in patients with severe aortic stenosis) registry, a Japanese multicenter registry, enrolled 3815 consecutive patients with severe aortic stenosis. There were 405 hemodialysis patients (initial aortic valve replacement [AVR] group: N=135 [33.3%], and conservative group: N=270) and 3410 nonhemodialysis patients (initial AVR group: N=1062 [31.1%], and conservative group: N=2348). The median follow-up duration after the index echocardiography was 1361 days, with 90% follow-up rate at 2 years. The cumulative 5-year incidence of all-cause death was significantly higher in hemodialysis patients than in nonhemodialysis patients in both the entire cohort (71% versus 40%, P<0.001) and in the initial AVR group (63.2% versus 17.9%, P<0.001). Among hemodialysis patients, the initial AVR group as compared with the conservative group was associated with significantly lower cumulative 5-year incidences of all-cause death (60.6% versus 75.5%, P<0.001) and sudden death (10.2% versus 31.7%, P<0.001). Nevertheless, the rate of aortic valve procedure-related death, which predominantly occurred within 6 months of the AVR procedure, was markedly higher in the hemodialysis patients than in the nonhemodialysis patients (21.2% and 2.3%, P<0.001).

CONCLUSIONS

Among hemodialysis patients with severe aortic stenosis, the initial AVR strategy as compared with the conservative strategy was associated with significantly lower long-term mortality risk, particularly the risk for sudden death, although the effect size for the survival benefit of the initial AVR strategy was smaller than that in the nonhemodialysis patients.

Higher visit-to-visit intra-dialytic blood pressure is associated with the progression of aortic valve stenosis in chronic hemodialysis patients

Aortic valve stenosis (AS) is a frequent complication contributing to poor prognosis in chronic hemodialysis (CHD) patients. High blood pressure (BP) is known to be associated with AS progression in the general population. In CHD patients, however, BP varies during and between hemodialysis sessions with ultrafiltration volume or inter-dialytic weight gain; therefore it is difficult to characterize the BP status with a conventional single measurement. Our purpose was to clarify the BP variables affecting AS progression in CHD patients. We retrospectively enrolled 32 consecutive CHD patients with AS [aortic valve area (AVA), 1.3 ± 0.3 cm(2); mean age 69 ± 8 years] who had serial transthoracic echocardiographic studies at least 6 months apart (mean 23 ± 9 months). AS progression was evaluated using absolute reduction in AVA per year. Pre-dialytic and intra-dialytic (every hour during sessions) BPs throughout the 3 consecutive visits were used to determine each patient's BP status. We calculated the mean values of pre-dialytic and intra-dialytic BPs and their variability. In univariate analysis, mean visit-to-visit pre-dialytic and intra-dialytic BP were associated with AS progression, whereas all variables of BP variability were not. Multiple regression analysis indicated that only mean visit-to-visit intra-dialytic systolic and diastolic BP remained independently associated with AS progression after adjustment for age, sex, hypertension, hypercholesterolemia, diabetes mellitus, and serum parathyroid hormone (p < 0.05). Although BP regulation in CHD patients is complex and multifactorial, mean visit-to-visit intra-dialytic BP was independently associated with AS progression. Prospective studies are necessary before considering intra-dialytic BP as a potential target for therapy.

Enhanced expression of hemoglobin scavenger receptor and heme oxygenase-1 is associated with aortic valve stenosis in patients undergoing hemodialysis

A high prevalence and a rapid progression of aortic valve stenosis (AS) in patients undergoing hemodialysis (HD) has been reported. In these circumstances, intraleaflet hemorrhage of aortic valve may be related to the development of AS in HD patients. We immunohistochemically examined the relationship among intraleaflet hemorrhage, neovascularization, hemoglobin scavenger receptor (CD163), and heme oxygenase-1 (HO-1) using surgically resected aortic valve specimens from AS patients undergoing HD. The study population consisted of 26 HD patients and 25 non-HD patients with severe AS who had undergone aortic valve replacement. Frozen aortic valve samples surgically obtained from AS patients were stained immunohistochemically with antibodies against smooth muscle cells, macrophages, glycophorin-A (a protein specific to erythrocyte membranes), CD31, CD163, and HO-1. Morphometric analysis demonstrated that the CD163-positive macrophage score, the number of CD31-positive microvessels, and the percentage of glycophorin-A and HO-1-positive area were significantly higher in HD patients than in non-HD patients (CD163-positive macrophage score, P < 0.0001; CD31-positive microvessels, P < 0.0001; glycophorin-A, P < 0.0001; HO-1, P < 0.0001). Double immunostaining for CD163 or HO-1 and macrophages revealed that the majority of CD163- or HO-1-positive cells were macrophages. Furthermore, CD163-positive macrophage score was positively correlated with glycophorin-A, HO-1-positive area, and the number of CD31-positive microvessels (glycophorin-A, R = 0.66, P < 0.0001; HO-1, R = 0.50, P < 0.0005; microvessels, R = 0.38, P < 0.01). These findings suggest a positive association among intraleaflet hemorrhage, neovascularization, and enhanced expression of CD163 and HO-1 as a response to intraleaflet hemorrhage in stenotic aortic valves in AS patients undergoing HD.

Selection of artificial valve for the patients on hemodialysis

The selection of artificial valve for the hemodialysis patients is still controversial. Initially ACC/AHA guideline recommended using mechanical valve because of concern on the durability of bioprosthesis after replacement on the dialysis patients; however, revised guideline deleted that recommendation. Although many reports recognized rapid deterioration of bioprosthesis mainly due to calcification after valve replacement, there is no difference on survival between both types of valve. The recently conducted meta-analysis reported the same conclusions. Actually the long-term survival of the dialysis patients is poorer than that of non-dialysis people; however, it differs according to the etiology of renal failure. For example, the long-term survival of the non-diabetic patients seems longer than that of diabetic patients requiring longer durability of artificial valve. According to ACC/AHA guideline and the meta-analysis, surgeon should not hesitate to use bioprosthetic valve; however, surgeon should consider stratification of the dialysis patients by prediction for the long survival of each patient.

Progression of aortic stenosis in elderly patients over long-term follow up

BACKGROUND

The natural history of aortic stenosis (AS) in elderly patients remains poorly defined. In an elderly cohort over long-term follow-up, we assessed: 1) rates and predictors of hemodynamic progression and 2) composite aortic valve replacement (AVR) or death endpoint.

METHODS

Consecutive Department of Veterans' Affairs patients with AS (>60 years) were prospectively enrolled between 1988 and 1994 (n=239) and followed until 2008. Patients with ≥ 2 trans-thoracic echocardiograms >6 months apart were included in the progression analysis (n=147). Baseline demographics, comorbidities and echocardiography parameters were recorded. Follow-up was censored at AVR/death.

RESULTS

The age of patients was 73 ± 6 years; 82% were male. Baseline AS severity was mild (67%), moderate (23%) and severe (10%). Follow-up was 6.5 ± 4 years (range: 1-17 years). Annualized mean aortic valve gradient progression rates were: mild AS 4 ± 4 mmHg/year; moderate AS 6 ± 5 mmHg/year and severe AS 10 ± 8 mmHg/year (p<0.001). Five-year event-free survival was 66 ± 5%, 23 ± 7% and 20 ± 10% for mild, moderate and severe AS respectively. Progression to severe AS occurred in 35% and 74% of patients with mild and moderate AS respectively. Independent predictors of rapid progression were: baseline AS severity (per grade) (OR 2.6, p=0.001), aortic valve calcification (per grade) (OR 2.1, p=0.01), severe renal impairment (OR 4.0, p=0.04) and anemia (OR 2.3, p=0.05).

CONCLUSIONS

In elderly patients, hemodynamic progression of AS is predicted by AS severity, renal function, aortic valve calcification and history of anemia. These factors identify patients at high risk of rapid hemodynamic progression, for whom more frequent clinical and echocardiographic surveillance is advisable.

Current state of symptomatic aortic valve stenosis in the Japanese elderly

BACKGROUND

There have been few reports regarding treatment selection and prognosis of symptomatic aortic valve stenosis (AS) in the elderly in Japan.

METHODS AND RESULTS

Sixty-one patients hospitalized between January 2000 and December 2007 for symptomatic severe AS were investigated. The average observation period was 27 months. Thirty-seven patients (61%) were diagnosed with AS for the first time on hospitalization. Thirty-six patients had onset of symptoms within 1 month before admission. Thirty-six patients received aortic valve replacement (group S) and 25 received medical therapy (group M). The patients in group M were older than those in group S (84.1 ± 5.3 years vs. 74.2 ± 4.6 years, P<0.001). Maximum flow velocity measured by echocardiography was lower in group M (4.5 ± 0.3 m/s vs. 4.9 ± 0.5 m/s, P<0 .01), but there was no difference in valve area between the 2 groups (0.62 ± 0.19 cm² vs. 0.57 ± 0.15 cm², P=0.12). One-year mortality rate derived from the Kaplan-Meier curve was higher in group M than group S (53.1% vs. 6.4%, respectively). On multivariate analysis, the only independent favorable prognostic factor was aortic valve replacement (HR: 0.02, 95%CI: 0.01-0.15, P<0.01).

CONCLUSIONS

Medical therapy is often selected for treatment of symptomatic AS in the elderly, but the prognosis is very poor. Symptomatic severe aortic stenosis should be treated surgically, or with transcatheter aortic valve implantation in cases with high surgical risk.

Parathyroid hormone and systolic blood pressure accelerate the progression of aortic valve stenosis in chronic hemodialysis patients

BACKGROUND

Aortic valve stenosis (AS) is a frequent complication contributing to poor prognosis in chronic hemodialysis (CHD) patients. However, little is known regarding the risk factors affecting AS progression. The purpose of this study was to define risk factors affecting AS progression in CHD patients.

METHODS

We retrospectively investigated 34 consecutive CHD patients with asymptomatic AS (mild in 9, moderate in 20, severe in 5; aortic valve area (AVA), 1.31±0.31cm(2); mean age, 69±8years) who underwent followed-up paired transthoracic echocardiography with period of at least six months apart (22±9months). AS progression was evaluated using the absolute reduction in AVA per year.

RESULTS

CHD patients were divided into 20 patients with rapid progression (AVA reduction, >0.1cm(2) per year) and 14 with slow progression (AVA reduction, ≤ 0.1cm(2) per year). Serum parathyroid hormone (PTH) level was significantly higher in patients with rapid progression than in those with slow progression [343±489pg/ml vs. 76±80pg/ml, P<0.05]. In univariate analysis, AS progression by absolute AVA reduction per year was associated with age, PTH level, initial AVA, systolic blood pressure (SBP), diastolic blood pressure, total cholesterol, and left ventricular diameter at end-diastole and end-systole. Multiple regression analysis indicated that serum PTH level and SBP remained independently associated with AS progression.

CONCLUSIONS

AS progression was accelerated in the presence of high PTH and SBP. Careful monitoring and intensive treatment of these parameters may have a beneficial effect on secondary prevention in CHD patients.

Aortic stenosis

In developed countries, aortic stenosis is the most prevalent of all valvular heart diseases. A manifestation of ageing, the disorder is becoming more frequent as the average age of the population increases. Symptomatic severe disease is universally fatal if left untreated yet is consistent with a typical lifespan when mechanical relief of the stenosis is provided in a timely fashion. Management of mild disease, severe asymptomatic disease, and far advanced disease, and the effect of new percutaneous treatments, provide both controversy and exciting promise to care of patients with aortic stenosis. We discuss these issues in this Review.

ACE inhibition attenuates uremia-induced aortic valve thickening in a novel mouse model

Background

We examined whether impaired renal function causes thickening of the aortic valve leaflets in hyperlipidemic apoE-knockout (apoE^-/-) mice, and whether the putative effect on the aortic valves could be prevented by inhibiting the angiotensin-converting enzyme (ACE) with enalapril.

Methods

Thickening of the aortic valve leaflets in apoE^-/- mice was induced by producing mild or moderate chronic renal failure resulting from unilateral nephrectomy (1/2 NX, n = 18) or subtotal nephrectomy (5/6 NX, n = 22), respectively. Additionally, the 5/6 NX mice were randomized to no treatment (n = 8) or enalapril treatment (n = 13). The maximal thickness of each leaflet was measured from histological sections of the aortic roots.

Results

Leaflet thickness was significantly greater in the 5/6 NX mice than in the 1/2 NX mice (P = 0.030) or the unoperated mice (P = 0.003). The 5/6 NX mice treated with enalapril had significantly thinner leaflets than did the untreated 5/6 NX mice (P = 0.014).

Conclusion

Moderate uremia causes thickening of the aortic valves in apoE^-/- mice, which can be attenuated by ACE inhibition. The nephrectomized apoE^-/- mouse constitutes a new model for investigating the mechanisms of uremia-induced aortic valve disease, and also provides an opportunity to study its pharmacologic prevention.

Risk factors for progression of calcific aortic stenosis and potential therapeutic targets

Current thought regarding the progression of calcific aortic stenosis (AS) is presented. After summarizing contemporary ideas about AS pathogenesis, the present article examines the factors that may affect disease progression. Data indicate that this process may be accelerated by aortic valve structure, degree of valvular calcification, chronic renal insufficiency and cardiovascular risk factors such as diabetes and dyslipidemia. Finally, the present review discusses potential therapeutic targets to slow AS progression.

Association of creatinine clearance and in-hospital mortality in patients with acute coronary syndromes: the GREECS study

BACKGROUND

The relationship between renal dysfunction and mortality in patients with myocardial infarction (MI) has been extensively investigated, but there are limited data about this relationship in patients presenting with non-ST-segment-elevation MI and unstable angina. Therefore, the aim of the present study was to investigate whether renal insufficiency is an independent predictor for in-hospital mortality among such patients.

METHODS AND RESULTS

Two thousand a hundred and seventy-two patients presenting with acute coronary syndrome (ACS) in 6 Greek hospitals were enrolled. Creatinine clearance rates were estimated by the Cockcroft-Gault formula. Five percentage of patients presented with severe renal dysfunction, 27% with moderate dysfunction and the other 68% were normal. Patients with moderate or severe renal dysfunction were older, more likely to be women and more likely to have history of hypertension and diabetes mellitus compared with those with normal renal function. In comparison with patients with normal renal function, those with moderate and severe renal dysfunction were respectively 3- and 12-fold more likely to die. Moreover, moderate and severe renal insufficiency continued to be a prognostic factor for mortality, even after controlling for potential confounders.

CONCLUSIONS

Creatinine clearance rate is an important independent predictor of in-hospital mortality, so patients with ACS complicated by renal dysfunction should receive more aggressive medical care.

The Simultaneous Assessment of Aortic Valve Area and Coronary Artery Stenosis Using 16-Slice Multidetector-Row Computed Tomography in Patients With Aortic StenosisComparison With Echocardiography

BACKGROUND

Recent advancements in 16-slice multidetector-row computed tomography (16-slice MDCT) provide for non-invasive assessment of not only coronary artery disease (CAD), but also myocardial properties and the anatomy of the whole heart. The purpose of the present study was to investigate whether the aortic valve area (AVA) in patients with aortic stenosis (AS) assessed by 16-slice MDCT corresponds to echocardiographic assessment and to evaluate simultaneously the clinical accuracy in detecting CAD with 16-slice MDCT.

METHODS AND RESULTS

The AVA of 29 consecutive AS patients with transthoracic echocardiography (TTE) and 16-slice MDCT were analyzed. The AVA was estimated by means of the continuity equation method in 2-dimensional echocardiography (DE) and the quantitative planimetric method after multi-planar reformation in 16-slice MDCT. Concomitantly, the severity of the coronary artery stenosis was assessed by 16-slice MDCT. In the present study, the AVA assessed by TTE and 16-slice MDCT was 1.34+/-0.32 cm(2) and 1.38+/-0.32 cm(2), respectively. Regression analysis showed that the AVA in patients with AS determined by 16-slice MDCT correlated well with those determined by 2-DE (r=0.96, p<0.001). Significant coronary artery stenosis of more than 50% diameter reduction was present in 48% of the study population.

CONCLUSIONS

In patients with AS, the analysis of the severity of the AVA by 16-slice MDCT provides a feasible and accurate estimation with the concomitant evaluation of CAD.