The assessment of pressure-volume relationship during exercise stress echocardiography predicts left ventricular remodeling and eccentric hypertrophy in patients with chronic heart failure.

BACKGROUND: The contractile response of patients with heart failure (HF) may be assessed by exercise stress echocardiography (ESE)-derived indexes. We sought to test whether ESE parameters are useful to identify the risk of adverse left ventricular (LV) remodeling in patients with chronic HF and reduced or mildly reduced LV ejection fraction (EF). METHODS: We enrolled 155 stabilized patients (age: 62 ± 11 years, 17% female, coronary artery disease 47%) with chronic HF, LV EF ≤50% and LV end-diastolic volume index > 75 ml/m2. All patients underwent a symptom-limited graded bicycle semi-supine ESE, with evaluation of peak stress LV EF, end-systolic pressure-volume relation (ESPVR, i.e. LV elastance) and cardiac power output to LV mass (CPOM). A complete echocardiographic study was performed at baseline and after 6 ± 3 months. Adverse LV remodeling was defined as the association of eccentric LV hypertrophy (LV mass: ≥115 g/m2 for male and ≥ 95 g/m2 for women, and relative wall thickness < 0.32) with an increase in LV end-systolic volume index ≥10% at six months. RESULTS: Adverse LV remodeling was detected in 34 (22%) patients. After adjustment for clinical, biochemical and echocardiographic data, peak ESPVR resulted in the most powerful independent predictor of adverse LV remodeling (OR: 12.5 [95% CI 4.5-33]; p < 0.0001) followed by ischemic aetiology (OR: 2.64 [95% 1.04-6.73]; p = 0.04). CONCLUSION: In patients with HF and reduced or mildly reduced EF, a compromised ESE-derived peak ESPVR, that reflects impaired LV contractility, resulted to be the most powerful predictor of adverse LV remodeling.

Left Ventricular Mass and Thickness: Why Does It Matter?

Several left ventricular geometric patterns have been described both in healthy and pathologic hearts. Left ventricular mass, wall thickness, and the ratio of wall thickness to radius are important measures to characterize the spectrum of left ventricular geometry. For clinicians, an increase in left ventricular mass is the hallmark of left ventricular hypertrophy. Although pathologic hypertrophy initially can be compensatory, eventually it may become maladaptive and evolve toward progressive left ventricular dysfunction and heart failure. In particular, patients who show left ventricular dilation and hypertrophy in association with a low relative wall thickness are likely to carry the highest risk.

Value of combined cardiopulmonary and echocardiography stress test to characterize the haemodynamic and metabolic responses of patients with heart failure and mid-range ejection fraction.

AIMS: To characterize heart failure (HF) with mid-range ejection fraction (HFmrEF), combining cardiopulmonary exercise test, and exercise stress echocardiography. METHODS AND RESULTS: We studied 169 consecutive subjects (age 62.3 ± 11 years; 74% male): 30 healthy controls, 45 patients with HF and preserved EF (HFpEF), 40 HFmrEF, and 54 with HF and reduced EF (HFrEF). Left ventricular (LV) stroke volume (SV), EF, elastance, global longitudinal strain, E/E', oxygen consumption (VO2), and arterial-venous oxygen content difference (AVO2diff) were measured in all exercise stages. HFmrEF revealed baseline features intermediate between HFrEF and HFpEF, except for B-type natriuretic peptide levels, which was similar to HFpEF and significantly lower than HFrEF. Peak VO2 was not significantly different between HF groups. HFrEF exhibited a significantly lower peak SV as compared to either HFpEF or HFmrEF (74.3 ± 21.8 mL vs. 88.0 ± 17.4 mL and 96.5 ± 25.1 mL; P < 0.01), whereas peak heart rate was not significantly different between HF groups. A significantly reduced AVO2diff at peak exercise was apparent in HFpEF and HFmrEF (15.2 ± 3.3 mL/dL and 13.3 ± 4.2 mL/dL) vs. HFrEF (17.±6.6 mL/dL; P < 0.01), whereas no significant difference was reported between HFpEF and HFmrEF. Multivariate analysis in the overall population and all groups revealed peak parameters as independent predictors of peak VO2 (R2 = 0.90, P < 0.0001); AVO2diff showed the largest standardized regression coefficient. CONCLUSION: In HFpEF and HFmrEF, effort intolerance is predominantly due to peripheral factors (AVO2diff), whereas in HFrEF peak VO2 is restricted by low increases in SV. Individual therapy according to which component of VO2 is more impaired is advisable.

Appropriate use criteria in clinical routine practice: implications in a nuclear cardiology lab.

The efforts for a broad application of the appropriate use criteria to reduce inappropriate nuclear stress testing have frequently been unsuccessful and the reported rates of inappropriateness have varied widely between studies. We sought to analyze the criteria of clinical appropriateness of a cohort of consecutive patients referred to our nuclear cardiology laboratory to perform stress myocardial perfusion imaging (MPI) and to assess the relationships between test appropriateness and the evaluation of ischaemia. A cohort of 251 consecutive patients, admitted to our Institute from January to March 2015, who underwent stress/rest MPI on a dedicated cardiac camera equipped with cadmium-zinc-telluride detectors, was selected. The level of clinical appropriateness of each MPI test was categorized in each patient according to the AUC criteria. According to the accepted criteria, the majority of the MPI stress-tests could be classified as clinically appropriate (218 of 251, 87 % of the tests), while only 16 (6 %) and 17 (7 %) resulted of uncertain appropriateness or clearly inappropriate, respectively. Of the 251 appropriate tests, 22 (10 %), 65 (30 %), and 131 (60 %) showed the presence of a mild (SDS < 4), moderate (4 ≥ SDS < 7), and severe (SDS ≥ 7) ischemic burden, respectively, while none of the inappropriate test showed moderate-to-severe ischaemia (P < 0.001 for comparisons). The rate of inappropriate MPI tests is considerably low in a high-volume laboratory. Appropriate and inappropriate studies identify patients at high and low probability of significant ischemia, respectively, providing insights on the effects of the level of appropriateness on stress-test results.