The value of serial echocardiography in risk assessment of patients with paroxysmal atrial fibrillation

Progression from paroxysmal to persistent atrial fibrillation (AF) is associated with increased morbidity and mortality. We examined the association of left atrial (LA) remodeling by serial echocardiography, and AF progression over an extended follow-up period. Two-hundred ninety patients (mean age 61  ±  11 years, 73% male) who underwent transthoracic echocardiography performed at first presentation for non-valvular paroxysmal AF (PAF) and repeat echocardiogram 1-year later, were followed for progression to persistent AF. LA and left ventricular (LV) dimensions, volumes, LA reservoir, conduit and booster pump strains, LV global longitudinal systolic strain (GLS) assessed by 2D speckle tracking, and PA-TDI (time delay between electrical and mechanical LA activation- reflecting the extent of LA fibrosis) were compared on serial echocardiography. Sixty-nine (24%) patients developed persistent AF over a mean follow-up period of 6.3 years. At baseline, patients with subsequent persistent AF had larger LA dimensions (46 mm vs. 42 mm, p < 0.001), indexed LA volumes (41 ml/m2 vs. 34 ml/m2, p < 0.001), lower LA reservoir and conduit strain (17.6% vs. 27.6%, p < 0.001; 10.5% vs. 16.3%, p < 0.001; respectively) and longer PA-TDI (155 ms vs. 132 ms, p < 0.001) compared to the PAF group. Patients with subsequent persistent AF showed over time significant enlargement in LA volumes (from 37.7 ml/m2 to 42.4 ml/m2, p < 0.001), lengthening of PA-TDI (from 142.2 ms to 162.2 ms, p = 0.002), and decline in LA reservoir function (from 21.9% to 18.1%, p = 0.024) after adjusting for age, gender, diabetes and LV GLS. There were no changes in LA diameter, LA conduit or booster pump function. Conversely, the PAF group showed no decline in LA function. Patients who developed persistent AF had larger LA size and impaired LA function and atrial conduction times at baseline, compared to patients who remained PAF. Over the 1-year time course of serial echocardiographic evaluation, there was progression of LA remodeling in patients who subsequently developed persistent AF, but not in patients who remained in PAF.

Sex differences in prognosis of significant secondary mitral regurgitation

AIMS

Secondary mitral regurgitation (MR) is more frequent in men than in women. However, little is known about differences in prognosis between men and women with secondary MR. The objective of this study is to investigate the sex distribution of secondary MR and the prognostic differences between sexes.

METHODS

Patients with significant secondary MR, of both ischaemic and non-ischaemic aetiologies, were identified through the departmental electronic patient files and retrospectively analysed. The primary endpoint was all-cause mortality.

RESULTS

A total of 698 patients (mean age 66 ± 11 years) with significant secondary MR were included: 471 (67%) men and 227 (33%) women. Ischaemic heart failure was significantly more common in men (61%), whereas non-ischaemic heart failure was more prevalent in women (63%). Women had significantly smaller left ventricular (LV) volumes when compared with men and more preserved LV systolic function when assessed with LV global longitudinal strain (GLS; 8.5 ± 4.1% vs. 7.5 ± 3.6%; P = 0.004). Women more often underwent surgical mitral valve repair (34%) when compared with men (26%), although no differences were observed for transcatheter mitral valve repair. During a median follow-up of 57 [interquartile range 29-110] months, 373 (53%) patients died. Women showed significantly lower mortality rates at 1-, 2- and 5-year follow-up (9%, 16% and 33% vs. 10%, 20% and 42%) when compared with men (P = 0.001).

CONCLUSIONS

Significant secondary MR is more frequently observed in men as compared with women and is associated with worse prognosis.

Characteristics and Prognosis of Patients With Nonvalvular Atrial Fibrillation and Significant Valvular Heart Disease Referred for Electrical Cardioversion

Valvular atrial fibrillation (AF) is defined as AF in the presence of mitral stenosis or mechanical valve prosthesis. However, there are patients with AF who have significant native valvular heart disease (VHD) others than mitral stenosis that are classified as nonvalvular AF. The characteristics and prognostic implications of these entities have not been extensively studied. Of 1,885 AF patients referred for electrical cardioversion (64 ± 13years, 71% male), 171 (9.1%) had valvular AF (any grade of mitral stenosis or mechanical/biological valve prostheses) and 1,714 patients were identified as nonvalvular AF, of whom 329 (17.5%) had significant left-sided VHD. Patients with nonvalvular AF but with significant left-sided VHD were older, more frequently women and had more co-morbidities compared with the other groups. Furthermore, nonvalvular AF patients with significant left-sided VHD showed the worst left ventricular systolic function and largest left atrial volumes. During a median follow-up of 64 months (interquartile range: 33 to 96 months), 488 patients presented with the combined endpoint of all-cause mortality, heart failure hospitalization, and ischemic stroke. Patients with nonvalvular AF and with significant left-sided VHD had more events of heart failure whereas patients with valvular AF had higher all-cause mortality events. There were no differences in ischemic stroke events. Type of AF was not associated with outcomes after correcting for echocardiographic variables. In conclusion, the frequency of AF patients with significant VHD is relatively high. The consequences of VHD and AF on cardiac structure and function are more important determinants of adverse outcome than the type of AF.

Progression of Left Ventricular Myocardial Dysfunction in Systemic Sclerosis: A Speckle-tracking Strain Echocardiography Study

OBJECTIVE

Cardiac involvement is a main cause of mortality in systemic sclerosis (SSc). Its detection remains challenging using conventional echocardiography and little is known about its potential progression. This study assessed changes in cardiac performance over time in a prospective cohort of patients with SSc, including echocardiographic speckle-tracking strain analysis.

METHODS

The study included 234 patients with SSc [196 women, age 52 ± 14 yrs, 165 limited SSc, time since diagnosis 5.2 yrs, interquartile range (IQR) 2.9-11.3]. Clinical variables, laboratory tests, pulmonary function tests, and echocardiographic measures were recorded at baseline and followup (median 2.3 yrs, IQR 1.3-3.9). Additionally, left ventricular (LV) systolic function was assessed with global longitudinal strain (GLS) by echocardiographic speckle-tracking analysis.

RESULTS

At followup, GLS had significantly worsened (-21% ± 2 vs -19% ± 2, p < 0.001) while LV ejection fraction had not changed (62% ± 7 vs 61% ± 8, p = 0.124). In particular, 39 patients showed a significant deterioration of GLS as defined by a ≥ 15% decrease, which was accompanied by a concomitant worsening of proximal muscle weakness, lung fibrosis, renal function, LV diastolic function, and right ventricular systolic function. Baseline variables associated with ≥ 15% deterioration in GLS were proximal muscle weakness (OR 3.437, 95% CI 1.13-10.43, p = 0.020), decreased DLCO (OR 3.621, 95% CI 1.25-10.51, p = 0.049), and LV diastolic dysfunction (OR 2.378, 95% CI 1.07-5.27, p = 0.033).

CONCLUSION

In patients with SSc, progression of LV systolic dysfunction was demonstrated by GLS but not by LV ejection fraction. Proximal muscle weakness, DLCO, and LV diastolic dysfunction may identify patients at risk for progressive LV systolic dysfunction and in need of closer cardiac monitoring.

Relation of Echocardiographic Markers of Left Atrial Fibrosis to Atrial Fibrillation Burden

In patients with atrial fibrillation (AF), left atrial (LA) fibrosis is a major determinant of the progression to, and burden of AF. LA reservoir strain and total atrial conduction time (PA-TDI) reflect LA fibrotic content. We aimed to investigate the relation between LA reservoir strain and PA-TDI in AF patients and control subjects. Six-hundred two patients (mean age 56 years, 53% men) with first episode of AF and 342 controls (mean age 64 years, 71% men) without structural heart disease underwent echocardiography. LA volumes, PA-TDI, LA reservoir strain, and left ventricular global longitudinal strain (GLS) were compared. Compared with controls, patients with paroxysmal AF and patients with persistent AF had longer PA-TDI (128 ± 25 millisecond, 140 ± 31 millisecond, and 154 ± 33 millisecond, respectively; p <0.001) and a progressive decline in LA reservoir strain (36.9 ± 11.6%, 29.8 ± 13.4%, 24.2 ± 12.3%, respectively; p <0.001). LA reservoir strain was negatively correlated with PA-TDI (r = -0.43, p <0.001). On multivariate analyses, LA reservoir strain, diabetes mellitus, and burden of AF were independent correlates of PA-TDI (R² = 0.23, p <0.001); whereas only PA-TDI was an independent correlate of LA reservoir strain (R² = 0.43, p <0.001); controlling for age, hypertension, coronary artery disease, body mass index, severity of mitral regurgitation, left ventricular global longitudinal strain, and LA volume. In conclusion, PA-TDI and LA reservoir strain are negatively correlated in all subjects, irrespective of the presence or burden of AF. Patients with persistent AF have longer PA-TDI and impaired LA reservoir strain compared with paroxysmal AF and controls, suggesting increasing burden of fibrosis and LA structural remodeling in the progression of AF.

Integrated imaging of echocardiography and computed tomography to grade mitral regurgitation severity in patients undergoing transcatheter aortic valve implantation

Aims

Quantitative mitral regurgitation (MR) grading remains challenging. This study evaluated the concept of integrating echocardiography and computed tomography for grading MR severity. Specifically, an integrated parameter was developed that combines the true cross-sectional mitral regurgitant orifice area (ROA) assessed with multi-detector row computed tomography (MDCT) with flow data from echocardiography.

Methods and results

Systolic MDCT data of 73 patients, referred for transcatheter aortic valve implantation (TAVI) who also had MR, were evaluated. The MDCT systolic phase with the smaller left ventricular volume and the largest mitral regurgitant orifice was selected. Using planimetry, the mitral ROA was measured. The mitral ROA was multiplied with the velocity time integral of the MR jet on echocardiography for the calculation of the integrated regurgitant volume (RVol). MDCT analysis showed a mean mitral ROA of 11.3 ± 7.4 mm2 and a mean integrated RVol of 21.4 ± 14.7 mL/beat, whereas echocardiography showed a mean effective ROA and RVol of MR of 13.3 ± 8.2 mm2 and 23.9 ± 13.6 mL/beat, respectively. Compared with echocardiography, grading based on integrated mitral RVol resulted in reclassification of 10% of the patients from severe to non-severe MR and 14% of the patients from non-severe to severe MR.

Conclusions

Integrated mitral RVol is a quantitative parameter of MR severity by combining the true cross-sectional mitral ROA assessed with MDCT and Doppler mitral haemodynamics which resulted in a significant reclassification of MR grade in patients with severe aortic stenosis undergoing TAVR.

Restrictive Mitral Valve Annuloplasty: Prognostic Implications of Left Ventricular Forward Flow

BACKGROUND

Surgical mitral valve repair for severe secondary mitral regurgitation (MR) remains controversial. The association of MR reduction and changes in left ventricular (LV) hemodynamics with survival has not been investigated. We investigated the independent associates of outcomes in heart failure patients with severe secondary MR who underwent surgical mitral valve repair.

METHODS

Patients (n = 130, 62 ± 12 years old, 55% men) with chronic severe secondary MR and impaired LV ejection fraction (<0.50, mean 0.31 ± 0.10) treated with surgical mitral valve repair were included. Echocardiographic LV forward stroke volume and LV forward ejection fraction were measured at baseline and at discharge. All-cause mortality was the primary endpoint, and the combination of major adverse cardiac-related events and all-cause mortality was the secondary endpoint.

RESULTS

At hospital discharge, 77% of patients showed no residual MR and 23% showed mild MR. LV volumes reduced significantly, whereas LV ejection fraction remained unchanged. In contrast, LV forward stoke volume (53 ± 24 mL versus 64 ± 22 mL, p < 0.001) and LV forward ejection fraction (0.32 ± 0.16 versus 0.48 ± 0.24, p < 0.001) significantly increased at discharge. During a median follow-up of 3.44 years, 33 patients (29%) died and 40 had major adverse cardiac-related events. On multivariable analysis, LV forward stroke volume after repair was independently associated with all-cause mortality (hazard ratio 0.98, p = 0.047) and with the combined endpoint (hazard ratio 0.98, p = 0.045) after correcting for other baseline, procedural, and postrepair characteristics.

CONCLUSIONS

In patients with severe secondary MR treated with surgical repair, LV forward flow was independently associated with better survival and lower risk of the combined endpoint.

Echocardiographic associates of atrial fibrillation in end-stage renal disease

Background

The prevalence of atrial fibrillation (AF) in end-stage renal disease (ESRD) patients is relatively high. The present study evaluated the association between left atrial (LA) remodelling, including an increased size and myocardial fibrosis, and slow LA conduction and the occurrence of AF.

Methods

In 171 ESRD patients enrolled in the Implantable Cardioverter Defibrillators in Dialysis patients (ICD2) trial, the LA dimensions, LA conduction delay [as reflected by the time difference between P-wave onset on surface electrocardiogram and A'-wave on tissue Doppler imaging (PA-TDI)] and LA function were compared between patients who exhibited AF versus patients without AF. Based on ICD remote monitoring or clinical records, the occurrence of AF was detected.

Results

Of 171 patients, 47 (27%) patients experienced AF. Despite comparable left ventricular ejection fraction and prevalence of significant mitral regurgitation, patients with AF had significantly larger LA volume index (mean ± standard deviation) (29 ± 11 versus 23 ± 10 mL/m2, P = 0.001), longer PA-TDI duration (144 ± 30 versus 131 ± 27 ms, P = 0.010) and reduced late diastolic mitral annular velocity (A') (7.1 ± 2.8 versus 8.2 ± 2.4 cm/s, P = 0.012) compared with patients without AF. On multivariable analysis, larger LA volume index [odds ratio (OR) 1.04, 95% confidence interval (CI) 1.01-1.08, P = 0.017], longer PA-TDI duration (OR 1.02, 95% CI 1.00-1.03, P = 0.025) and reduced A' (OR 0.84, 95% CI 0.72-0.98, P = 0.025) were independently associated with AF after adjusting for age and left ventricle diastolic relaxation.

Conclusion

ESRD patients with AF show more advanced changes in the LA substrate than ESRD patients without AF.