Segmental wall-motion abnormalities of the left ventricle predict arrhythmic events in patients with nonischemic cardiomyopathy

Prognostic value of summed motion score assessed by gated SPECT myocardial perfusion imaging in patients with dilated cardiomyopathy

Background

The prognosis of patients with dilated cardiomyopathy (DCM) is poor and new indicators are urgently needed to predict lethal cardiac events. This study aimed to investigate the value of summed motion score (SMS) in predicting cardiac death of DCM patients using gated single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI).

Methods and results

Eighty-one patients with DCM who underwent 99mTc-MIBI gated SPECT MPI were retrospectively enrolled and were divided into cardiac death and survivor groups. The functional parameters of left ventricle including SMS were measured using quantitative gated SPECT software. During the follow-up period of 44 (25, 54) months, 14 (17.28%) cardiac deaths were observed. Compared with the survivor group, SMS was significantly higher in the cardiac death group. Multivariate cox regression analysis showed that SMS was an independent predictor for cardiac death (HR 1.34, 95% CI 1.02–1.77, P = 0.034). SMS also provided incremental prognostic value over other variables in the multivariate model as determined by likelihood ratio global chi-squared test. In the Kaplan-Meier survival analysis, the event-free survival rate was significantly lower in the high-SMS (HSMS) group than the low-SMS (LSMS) (log-rank P < 0.001). Furthermore, the area under curve (AUC) of SMS was larger than that of LVEF at the 12th month of follow-up (0.85 vs. 0.80, P = 0.045).

Conclusion

SMS is an independent predictor of cardiac death in DCM patients and provides incremental prognostic value. SMS might have higher predictive value than LVEF for early cardiac death.

Prognostic Impact of Segmental Wall Motion Abnormality in Patients With Idiopathic Dilated Cardiomyopathy

The clinical impact of left ventricular (LV) segmental wall motion abnormalities (SWMA) in patients with idiopathic dilated cardiomyopathy (IDCM) has not been well elucidated.Among 100 consecutive IDCM patients with follow-up visits, we enrolled 85 after excluding those with left bundle branch block and/or ventricular pacemaker implantation. LV wall motion was assessed using left ventriculography scored for 7 segments according to the American Heart Association classification as follows: 0, normokinesis; 1, hypokinesis; 2, akinesis; and 3, dyskinesis. SWMA were defined as a score dispersion of more than 1 degree among the segments.SWMA was exhibited by 26 patients. Kaplan-Meier curves demonstrated that the patients with SWMA (SWMA+) had a significantly higher cardiac event-free rate than the patients without SWMA (P < 0.001). Cox proportional hazards analysis showed that SWMA+ was an independent predictor of cardiac events (P = 0.03; hazard ratio = 3.38; 95% confidence interval [CI], 1.11-10.8). Furthermore, multiple regression analysis showed that SWMA+ was an independent predictor of decreased LV end-systolic dimension index after optimal pharmacotherapy (β = -0.24; 95%CI, -9.12 to -0.73; P = 0.02).SWMA is common in patients with IDCM and is independently associated with a poor prognosis and less morphometric and functional improvement of LV in response to pharmacotherapy.

Management of asymptomatic (occult) feline cardiomyopathy: Challenges and realities

BACKGROUND

Cardiomyopathy distinguishes a heterogeneous group of myocardial disorders that represent the most prevalent cause of feline heart disease. Etiology is uncertain and the natural history is presently unresolved. Hypertrophic cardiomyopathy is the most common of these conditions, and while the majority of affected cats are asymptomatic, a proportion is at risk to develop serious morbidities--the most devastating of which include congestive heart failure, arterial thromboembolism, and cardiac death. Predicting when or whether an asymptomatic cat might develop morbidity is hindered by lack of evidence-based clinical trials. Superimposed, these issues create an irresolvable predicament that presently confounds medical decision-making.

METHODS

Review of current perspectives for managing asymptomatic (occult) feline cardiomyopathy.

RESULTS

Complex pathophysiology and (likely) sarcomeric mutations give rise to heterogeneous cardiac phenotypes and variable clinical findings. Echocardiography remains the gold standard to clarify cardiac morphology. Frequently, however, detection of echocardiographic alterations--though often of unproven clinical significance--extrapolates by inference or implication a specter of disease, and with this, leads to a path of long-term treatment and testing. Presently, there is no proof that any particular therapy reduces morbidity or prolongs survival of cats affected with occult cardiomyopathy. Recently, however, evidence has accumulated to support the belief that certain prognostic indicators suggest risk for poor outcome. Accordingly, and in absence of evidence-based clinical trials, current practice has shifted to view therapy with the intent to target pathophysiology underlying documented or perceived clinical markers, whose presence portends high risk in certain patients. Affected animals and potentially siblings should be monitored using clinical testing that also takes into account age-related comorbidities.

CONCLUSIONS

Asymptomatic (occult) feline cardiomyopathy includes complex and heterogeneous diseases whose outcomes are challenging to predict. Review of available evidence-based treatment data leaves no uncertainties regarding drugs with established efficacy. There presently are none. Current management focuses upon identification of documented risk factors, individualized and tailored therapy, and cogent monitoring. Drugs most commonly considered in this paradigm include those that might reduce thromboembolic risk in cases with substantial left atrial enlargement or dysfunction, agents to counteract left ventricular remodeling, or medications that ameliorate systolic or diastolic dysfunction. Discovering reliable prognostic indicators may further improve stratification to identify patients at highest risk, or detect subsets that respond favorably. These issues shape the challenge to identify sensible preventative management and cost-effective, long-term monitoring strategies.

Diagnostic usefulness of quantitative tissue velocity imaging and anatomic M-mode echocardiography for coronary artery diseases: A pilot study

BACKGROUND AND OBJECTIVE

To explore the potential clinical usefulness and determine optimal diagnostic criteria of quantitative tissue velocity imaging and anatomic M-mode echocardiography in patients with coronary artery disease (CAD).

METHODS

We used quantitative tissue velocity imaging for the measurement of systolic myocardial velocity, and anatomic M-mode echocardiography for the measurement of ventricular wall-thickening fraction in 44 subjects with suspected CAD. Subjects were classified as patients if coronary angiography demonstrated a stenosis ≥ 50%, and as controls if it was strictly normal. The diagnostic criteria, sensitivity, and specificity were assessed by receiver-operator curves.

RESULTS

Controls had greater mean systolic myocardial velocity and ventricular wall-thickening fraction in the basal (6.59 ± 1.25 cm/s and 0.44 ± 0.05) and mid segment (5.23 ± 0.93 cm/s and 0.43 ± 0.04) than patients (5.02 ± 1.17 cm/s and 0.29 ± 0.04, 3.27 ± 1.29 cm/s and 0.29 ± 0.04, respectively, p < 0.001). Mid-segment ventricular wall-thickening fraction offered 95% sensitivity (95% CI 88.7% to 98.4%), and 98.3% specificity (95% CI 90.9% to 1.0) with an optimal cut-off point of 0.349, yielding better results than systolic myocardial velocity, which provided 83% sensitivity (95% CI 74.2% to 89.8%), 90% specificity (95% CI 79.5% to 96.2%), and optimal cut-off point 4.47. The combination of systolic myocardial velocity and ventricular wall-thickening fraction offered 97% sensitivity (95% CI 91.5% to 99.4%)

CONCLUSIONS

Mid-segment ventricular wall-thickening fraction might be suitable for the evaluation of patients with CAD.