Right ventricular dysfunction and dilatation in patients with mitral regurgitation: Analysis using ECG-gated multidetector row computed tomography

Pathological right ventricular changes in synthesized electrocardiogram in end-stage renal disease patients and their association with mortality and cardiac hospitalization: a cohort study

Background

Right ventricular (RV) function is an important prognostic predictor for end-stage renal disease (ESRD) patients. Non-invasive evaluation of RV function by simple electrocardiogram (ECG) is not yet evident. The purpose of this article was to investigate the presence and association of pathological right ventricular changes in synthesized ECG with cardiac hospitalization and mortality.

Methods

A prospective cohort study of 137 ESRD patients (mean age: 56 years) were recruited from the hemodialysis unit in An-Najah National University Hospital, Nablus, Palestine. Synthesized ECG was done right before the hemodialysis (HD) session. The pathological right ventricular changes were recorded for each patient. The relationship between pathological RV changes and mortality, cardiac and non-cardiac hospitalization was assessed through a 6-months follow-up period.

Results

Right ventricular Q wave was found in 2.2% of patients, while right ventricular ST elevation was found in 0.7% of patients, and right ventricular negative T wave was found in 0.7% of patients. During the 6-month period of follow-up, 36 (26.3%) patients were hospitalized, nine patients (6.6%) due to cardiac causes. A total of 8 (5.83%) patients died, out of those 4 patients (2.91%) due to cardiac causes. Using Fisher’s exact test, there was a significant association between pathological abnormalities in synthesized ECG and hospitalization among hemodialysis patients, (p = 0.047). Pathological changes in synthesized ECG were less prevalent in non-cardiac hospitalizations than in cardiac hospitalizations.

Conclusions

The presence of pathological RV synthesized ECG changes can predict cardiac hospitalization in ESRD patients. Synthesized ECG is a good available tool that can be easily performed in ESRD patients. To determine whether Synthesized ECG can be used as a screening tool for pathological RV changes in a dialysis patients, more research with a larger number of patients and a longer follow-up period is required.

Force distribution within the frame of self-expanding transcatheter aortic valve: Insights from in-vivo finite element analysis

We sought to assess the amount and distribution of force on the valve frame after transcatheter aortic valve replacement (TAVR) via patient-specific computer simulation. Patients successfully treated with the self-expanding Venus A-Valve and multislice computed tomography (MSCT) pre- and post-TAVR were retrospectively included. Patient-specific finite element models of the aortic root and prosthesis were constructed. The force (in Newton) on the valve frame was derived at every 3 mm from the inflow and at every 22.5° on each level. Twenty patients of whom 10 had bicuspid aortic valve (BAV) were analyzed. The total force on the frame was 74.9 N in median (interquartile range 24.0). The maximal force was observed at level 5 that corresponds with the nadir of the bioprosthetic leaflets and was 9.9 (7.1) N in all patients, 10.3 (6.6) N in BAV and 9.7 (9.2) N for patients with tricuspid aortic valve (TAV). The level of maximal force located higher from the native annulus in BAV and TAV patients (8.8 [4.8] vs. 1.8 [7.4] mm). The area of the valve frame at the level of maximal force decreased from 437.4 (239.7) mm² at the annulus to 377.6 (114.3) mm² in BAV, but increased from 397.5 (114.3) mm² at the annulus to 406.7 (108.9) mm² in TAV. The maximum force on the bioprosthetic valve frame is located at the plane of the nadir of the bioprosthetic leaflets. It remains to be elucidated whether this may be associated with bioprosthetic frame and leaflet integrity and/or function.

The cardiothoracic ratio: a neglected preoperative risk-stratified method for patients with rheumatic heart disease undergoing valve replacement surgery

OBJECTIVES

It is common for patients with rheumatic heart disease to have an enlarged heart. We investigated the prognostic value of cardiothoracic ratio (CTR) in patients with rheumatic heart disease undergoing valve replacement surgery.

METHODS

A total of 1772 patients were divided into 4 groups based on the quartiles of preoperative CTR: <0.56 (n = 349), 0.56-0.61 (n = 488), 0.61-0.66 (n = 449) and ≥0.66 (n = 486). The CTR was measured from postero-anterior chest radiographs. We then investigated the association between the CTR and adverse outcomes.

RESULTS

In-hospital mortality was 4.0% (71/1772). Analyses of receiver operating characteristic curves showed that, at a cut-off of 0.6, the CTR exhibited 66.2% sensitivity and 64.0% specificity for detecting in-hospital death (area under curve 0.671, P < 0.001). The prevalence of in-hospital death was 7.1% in males with a CTR >0.6, which was significantly higher in males without a CTR. A similar result was observed in females (1.9 vs 5.1%, P = 0.004). Multivariable regression showed that a CTR >0.6 was an independent predictor of in-hospital (odds ratio 2.36, P = 0.005) and 1-year mortality (hazard ratio 2.06, P = 0.006). Kaplan-Meier curves, for the cumulative rate of 1-year mortality among groups, indicated that the risk of death was increased if the CTR >0.6 (log-rank 16.36, P < 0.001).

CONCLUSIONS

CTR, as a simple and reproducible indicator, was identified as a prognostic factor for predicting poor outcomes in patients with rheumatic heart disease undergoing valve replacement surgery.

Treating patients with excessively large annuli with self-expanding transcatheter aortic valves: insights into supra-annular structures that anchor the prosthesis

BACKGROUND

Some patients referred for transcatheter aortic valve replacement (TAVR) have excessively large annuli (ELA) without device options according to current sizing charts. This retrospective study aims to summarize the presentation and outcomes of ELA patients receiving first-generation self-expanding valves.

METHODS

The TAVR database was reviewed in search for cases of self-expanding valves. Patients who had annuli exceeding the perimeter limit on the device sizing chart were referred to as the ELA group. Patients who had annuli within the range covered by the two largest sizes and received the corresponding valve size served as the control group (CG). Baseline, procedures, outcomes, and imaging characteristics on multislice computed tomography (MSCT), such as native anatomy and postimplant stent geometry, were compared.

RESULTS

A total of 28 patients were included in the ELA group and 82 in the CG. The patients in the ELA group were younger than those in the CG (72.5 ± 6.2 vs. 75.4 ± 5.8 years, P = 0.03). The median intended perimeter oversizing in relation to the annulus in the ELA group was much smaller than in the CG (-0.4 [-4.6, 4.1] % vs. 16.1 [11.7, 20.8] %, P < 0.01). The calcium burden in the aortic root was around 1.3-fold greater in the ELA group than the CG (756.0 [534.5, 1670.9] vs. 582.1 [310.3, 870.9] mm³, P = 0.01). The need for second valve implantation was higher in ELA (21.4% vs. 12.2%, P = 0.23) but no valve embolization was encountered. The 1‑year follow-up was comparable, including >mild paravalvular leak.

CONCLUSION

Under cautious patient selection using MSCT, TAVR with self-expanding valves in patients with ELA appears feasible. Supra-annular structures likely provide the extra anchoring.

Effect of concomitant aortic regurgitation on early hypo-attenuated leaflet thickening after transcatheter aortic valve replacement in patients with symptomatic severe aortic stenosis

OBJECTIVE

We hypothesize that different degree of pre-existing aortic regurgitation (AR) may affect the presence of hypo-attenuated leaflet thickening (HALT) after transcatheter aortic valve replacement (TAVR).

BACKGROUND

The mechanism of the presence of HALT post-TAVR is not fully understood.

METHODS

We retrospectively evaluated the post-procedural multi-slice computed tomography (MSCT) before discharge for evidence of HALT. Patients were grouped according to the degree of pre-existing AR. Baseline, native anatomy and procedure details were compared, then multivariate regression was performed.

RESULTS

MSCT analyzed was performed at a median of 6 days post-TAVR in 179 patients. HALT was detected in 10.6% of patients. After adjusting for variables that were significantly different between groups, pre-existing ≥ moderate AR was protective to the risk of HALT (OR 0.15, 95% CI 0.03-0.84, p = .03). Stratifying for factors that might explain the impact of pre-existing AR on HALT, patients with a small Sinus of Valsalva, non-eccentric remodeling and receiving a large bioprosthesis experienced a sevenfold higher risk for HALT (OR 7.16, 95% CI 2.05-25.08, p = .002).

CONCLUSIONS

Patients underwent TAVR with pre-existing ≥ moderate AR appeared to experience a lower incidence of early HALT compared to those patients with less than moderate AR, which may be explained by a larger Sinus of Valsalva and a higher proportion of LV eccentric remodeling.

CT compared to MRI for functional evaluation of the right ventricle: a systematic review and meta-analysis

OBJECTIVE

Right ventricular function (RVF) is a strong predictor of adverse cardiac events; however, the reference standard for RVF assessment, MRI, is limited in some patients for whom accurate evaluation of RVF is essential, like those with COPD or non-MR compatible metal implants. We conducted this meta-analysis to evaluate whether CT was as accurate as MRI for the assessment of RVF.

METHOD

We conducted a meta-analysis of studies retrieved from PubMed, Embase, and Cochrane Central searches to evaluate the differences and correlations between the following RVF parameters as measured by CT and MRI: end diastole volume (EDV), end systole volume (ESV), right ventricular ejection fraction (RVEF), and stroke volume (SV).

RESULTS

Sixteen studies that used disk summation (637 subjects) and three studies that used three-dimensional reconstruction were included. For the 16 studies, the pooled standard mean differences (95% confidence interval) were 1.04 (- 2.59, 4.67) for EDV, 1.22 (1.50, 3.95) for ESV, - 0.65 (- 2.60, 1.29) for RVEF, and - 0.37 (- 3.64, 2.90) for SV. The overall correlation coefficient (r) values were 0.98 for EDV, 0.95 for ESV, 0.98 for RVEF, and 0.97 for SV. The mean difference between the two methods was not statistically significant (overall effect Z test, p > 0.1).

CONCLUSION

CT can assess RVF with accuracy comparable to that of MRI. Thus, CT is a valid alternative to MRI.

KEY POINTS

• CT could help clinicians to assess RVF as accurately as MRI can, with satisfactory repeatability.

Right Ventricular Function in Left Heart Disease

Right ventricular (RV) function is an independent prognostic factor for short- and long-term outcomes in cardiac surgical patients. Patients with mitral valve (MV) disease are at increased risk of RV dysfunction before and after MV operations. Yet RV function is not part of criteria for decision making or risk stratification in this setting. The role of MV disease in the development of pulmonary hypertension (PHTN) and the ultimate impact of PHTN on RV function have been well described. Nonetheless, there are other mechanisms by which MV disease and MV surgery affect RV performance. Research suggests that PHTN may not be the most important determinant of RV dysfunction. Both RV dysfunction and PHTN have independent prognostic significance. This review explores the unique anatomic and functional features of the RV and the pathophysiologic and prognostic implications of RV dysfunction in patients with MV disease in the perioperative period.

Permanent pacemaker implantation after transcatheter aortic valve replacement in bicuspid aortic valve patients

BACKGROUND

Studies of permanent pacemaker implantation (PPI) after transcatheter aortic valve replacement (TAVR) specifically for bicuspid aortic valve (BAV) patients are lacking. We aim to delineate possible aspects that might affect the incidence of PPI in a retrospective cohort of BAV patients treated with early-generation self-expanding devices.

METHODS

A total of 80 patients with bicuspid morphology who successfully underwent TAVR by self-expanding devices without prior PPI were included. Baseline clinical, echocardiographic, and angiographic characteristics, procedural and post-procedural details were collected.

RESULTS

The incidence of PPI after early-generation self-expanding valves in this BAV cohort was 26.3%. Baseline characteristics were comparable between patients requiring PPI post-TAVR or not. Perimeter oversizing greater than 20% significantly increased the risk of PPI compared with an oversizing of 10-20% (OR 5.08 [1.22, 21.07], P = 0.03). The proportion of patients with a depth of implantation greater than 6 mm was significantly higher in those who required PPI (82.4% vs 54.3%, P = 0.04). When testing the impact of depth of implantation >6 mm and oversizing in different morphologies, only in type 1 bicuspid patients and by oversizing>20% increased the risk of PPI (OR 12.00 [1.25, 115.36], P = 0.03) compared with an oversizing of 10-20%.

CONCLUSIONS

Excessive perimeter oversizing in relation to aortic annulus and depth of implantation greater than 6 mm should be avoided to improve PPI post-TAVR for BAV patients receiving self-expanding devices, especially for type 1 BAV.

Balloon sizing during transcatheter aortic valve implantation : Comparison of different valve morphologies

BACKGROUND

Although balloon sizing has been found to be useful during transcatheter aortic valve implantation (TAVI), its effectiveness in patients with bicuspid aortic valve (BiAV) remains unknown.

METHODS

Patients who underwent balloon sizing were retrospectively identified. The study comprised 67 patients (61.2% with BiAV). Preprocedural hypothetical transcatheter heart valve (THV) sizing was based on multislice computed tomography (MSCT) measurements at the annulus. Changes in valve size after balloon sizing were reviewed. Postprocedural MSCT measurements and the grade of paravalvular aortic regurgitation (PAR) were compared.

RESULTS

When comparing patients with a BiAV and those with a tricuspid aortic valve (TiAV), there was no significant difference (p = 0.97) in the proportion of decreased (43.9% vs. 46.2%), unchanged (51.2% vs. 50.0%), or increased (4.9% vs. 3.8%) valve sizes chosen on the basis of MSCT findings. The anticipated annular sizing ratio for patients who received a smaller valve was 7.2% (3.5-10.5%) while it was 15.7% (12.5-19.0) for the others (p < 0.01), and no significant difference in the proportion of mild (or more severe) PAR cases was found between the groups (37.9% vs. 30.6%, p = 0.53 at the 1‑month follow-up). Stent frame expansion and eccentricity index were comparable between the BiAV and TiAV subgroups among patients who received a smaller THV after balloon sizing.

CONCLUSION

Balloon sizing is a useful tool that is complementary to the current gold standard of MSCT for THV size selection as well as for BiAV morphology assessment.

Transcatheter aortic valve replacement in patients with non-calcific aortic stenosis

AIMS

Limited information exists describing the results of transcatheter aortic valve replacement (TAVR) in patients with symptomatic severe non-calcific aortic stenosis (AS). We aimed to compare procedural, echocardiographic, and clinical outcomes among patients with non-calcific AS with those of senile calcific AS undergoing TAVR.

METHODS AND RESULTS

We retrospectively identified patients with non-calcific AS who received TAVR with self-expanding transcatheter heart valves in our centre. Clinical and echocardiographic outcomes, and post-procedural multi-detector computed tomography (MDCT) measures were compared to those in patients undergoing TAVR for calcific AS. Among 136 patients, 21 patients (15.4%) with native leaflet thickening and minimal calcification were identified (non-calcific group). The patients were significantly younger in the non-calcific group (70.0 [64.0-75.5] vs. 75.0 [69.0-78.0] years) with comparable STS-PROM scores (6.7 [4.8-8.9] vs. 8.2 [4.8-10.9] %). Predilation was performed less frequently (42.9% vs. 93.9%) and post-dilation more often (71.4% vs. 42.6%) in the non-calcific group. Both 30-day and one-year mortality were similar between groups (0% vs. 7.8% and 0% vs. 17.6%). Rates of post-implantation paravalvular leak ≥mild at six months (17.6% vs. 25.7%) were comparable despite lower implantation depth among non-calcific AS patients (10.9±5.7 vs. 7.2±4.3 mm) on post-implantation MDCT.

CONCLUSIONS

TAVR with self-expanding transcatheter heart valves appears to be safe and effective in patients with non-calcific AS.

Thrombocytopenia as a Preoperative Risk Assessment Tool in Patients With Rheumatic Heart Disease Undergoing Valve Replacement Surgery

BACKGROUND

Postoperative thrombocytopenia has been reported to be correlated with adverse events, but the prognostic value of baseline thrombocytopenia is unclear. This study was undertaken to evaluate the relationship between preoperative thrombocytopenia and adverse outcomes in patients with rheumatic heart disease who underwent valve replacement surgery.

METHODS AND RESULTS

A total of 1789 patients with rheumatic heart disease undergoing valve replacement surgery were consecutively enrolled and postoperatively followed up for 1 year. Patients were stratified on the basis of presence (n=495) or absence (n=1294) of thrombocytopenia (platelet count, <150×10⁹/L), according to hospital admission platelet counts. During the hospitalization period, 69 patients (3.9%) died. The in-hospital all-cause mortality rate was significantly higher in the thrombocytopenic group (6.9% versus 2.7%; P<0.001). Multivariate analyses revealed that thrombocytopenia was independently associated with in-hospital all-cause mortality (odds ratio, 2.21; 95% confidence interval, 1.29-3.80; P=0.004). Platelet counts could predict in-hospital all-cause mortality for patients both with and without previous atrial fibrillation (areas under the curve, 0.708 [P<0.001] and 0.610 [P=0.025], respectively). One-year survival was significantly lower in patients with thrombocytopenia compared with controls (91.3% versus 96.1%; log-rank=14.65; P<0.001). In addition, thrombocytopenia was an independent predictor for postoperative 1-year all-cause mortality in multivariate Cox regression analysis.

CONCLUSIONS

Platelet counts, as simple and inexpensive indexes, were reliable to be used as a preoperative risk assessment tool for patients with rheumatic heart disease undergoing valve replacement surgery.

Preoperative assessment of mitral valve abnormalities in left atrial myxoma patients using cardiac CT

Background

To retrospectively evaluate mitral valve abnormality in left atrial myxoma patients by using cardiac computed tomography (CT).

Material and methods

Cardiac CT was performed in 56 patients with left atrial myxoma and 50 controls. Tumor and mitral valve characteristics were analyzed. The mitral valve parameters differences were compared between patients with myxoma and controls, myxoma with or without mitral valve obstruction, different obstruction degrees, respectively. Receiver operating characteristic analysis was performed to determine the cut-off values of abnormal mitral valve parameters for myxoma patients. Multiple linear regression, logistic regression models and cox regression analysis were used to determine factors associated with mitral valve abnormalities, mitral obstruction, mitral regurgitation and postoperative recovery, respectively.

Results

Myxoma induced the dilation of mitral valve, with different results among different degrees of obstruction (p<0.001). Mitral valve parameters had relationship with myxoma parameters. The cut-off values for discriminating mitral valve abnormalities in myxoma patients were found. Some significant predictors for mitral obstruction were tumor pedicle-tumor volume and patient age (HR, 0.886-30.811; p = 0.011-0.043). Moreover, the predictor for mitral regurgitation was mitral annulus diameter in diastolic phase (HR, 20.862; 95%CI,1.331-327.100; p = 0.031). Some predictors associated with postoperative recovery of mitral regurgitation were age, mitral annulus area, mitral annulus diameter and mitral valve diameter cutoff value for diastolic phase (HR, 0.001-119.160; p = 0.012-0.028).

Conclusion

Cardiac CT is capable of quantitatively assessing myxoma characteristic and mitral valve abnormality induced by myxoma, thus providing guidance of operative management and postoperative evaluation.

Assessing right ventricular function in patients with hypertrophic cardiomyopathy with cardiac MRI: correlation with the New York Heart Function Assessment (NYHA) classification

Purpose

To determine whether 3.0-T magnetic resonance imaging (MRI) could assess right ventricular (RV) function in patients with hypertrophic cardiomyopathy (HCM), and if this assessment is correlated with the New York Heart Function Assessment (NYHA) classification.

Materials and Methods

Forty-six patients with HCM and 23 normal individuals were recruited. Left and right ventricular function parameters including end-diastolic and end-systolic volumes (EDV, ESV), stroke volume (SV) and ejection fraction (EF) and dimensions were measured and compared using 3.0-T MRI. RV function parameters between HCM patients and controls were compared using independent sample t tests. A one way ANOVA test with Bonferroni correction was used to determine significant differences among different NYHA groups. Receiver operating characteristic analyses calculated the sensitivity and specificity of RV dysfunction on MRI for the prediction of HCM severity.

Results

Statistical analysis revealed significant differences of left ventricular (LV) and RV volumetric values and masses between the HCM patients and controls (all p<0.05). Within the HCM group, the simultaneously decreased maximum RVEDD correlated well with the LVEDD (r = 0.53; p<0.001). The function and dimension parameters among Class I to III were not determined to be significantly different (all p>0.05). However, significant differences between the Class IV and I-III groups (all P<0.0167) indicated that the diastolic and systolic function in both the RV and LV were impaired in Class IV patients. ROC analyses identified the EDV, ESV and EDD of both the LV and RV with a high sensitivity cutoff value to predict the HCM patients with severe heart failure (Class IV) with high sensitivity and specificity.

Conclusions

RV involvements were comparable to those of LV global function impairments in patients with HCM. The presence of RV dysfunction and decreased dimension on the MRI helped to predict the severe symptomatic HCM with high sensitivity and specificity.