Left atrial conduit flow rate at baseline and during exercise: an index of impaired relaxation in HFpEF patients.

AIMS: In healthy subjects, adrenergic stimulation augments left ventricular (LV) long-axis shortening and lengthening, and increases left atrial (LA) to LV intracavitary pressure gradients in early diastole. Lower increments are observed in patients with heart failure with preserved ejection fraction (HFpEF). We hypothesized that exercise in HFpEF would further impair passive LV filling in early-mid diastole, during conduit flow from pulmonary veins. METHODS AND RESULTS: Twenty HFpEF patients (67.8 ± 9.8 years; 11 women), diagnosed using 2007 ESC recommendations, underwent ramped semi-supine bicycle exercise to submaximal target heart rate (∼100 bpm) or symptoms. Seventeen asymptomatic subjects (64.3 ± 8.9 years; 7 women) were controls. Simultaneous LA and LV volumes were measured from pyramidal 3D-echocardiographic full-volume datasets acquired from an apical window at baseline and during stress, together with brachial arterial pressure. LA conduit flow was computed from the increase in LV volume from its minimum at end-systole to the last frame before atrial contraction (onset of the P wave), minus the reduction in LA volume during the same time interval; the difference was integrated and expressed as average flow rate, according to a published formula. The slope of single-beat preload recruitable stroke work (PRSW) quantified LV inotropic state. 3D LV torsion (rotation of the apex minus rotation of the base divided by LV length) was also measurable, both at rest and during stress, in 10 HFpEF patients and 4 controls. There were divergent responses in conduit flow rate, which increased by 40% during exercise in controls (+17.8 ± 37.3 mL/s) but decreased by 18% in patients with HFpEF (-9.6 ± 42.3 mL/s) (P = 0.046), along with congruent changes (+1.77 ± 1.13°/cm vs. -1.94 ± 2.73°/cm) in apical torsion (P = 0.032). Increments of conduit flow rate and apical torsion during stress correlated with changes in PRSW slope (P = 0.003 and P = 0.006, respectively). CONCLUSIONS: In HFpEF, conduit flow rate decreases when diastolic dysfunction develops during exercise, in parallel with changes in LV inotropic state and torsion, contributing to impaired stroke volume reserve. Conduit flow is measurable using 3D-echocardiographic full-volume atrio-ventricular datasets, and as a marker of LV relaxation can contribute to the diagnosis of HFpEF.

Transcatheter aortic valve replacement acutely improves left ventricular mechanical efficiency in severe aortic stenosis: effects of different phenotypes.

AIM: Aortic stenosis is a frequent valvular disease, with transcatheter aortic valve implantation (TAVI) being performed when surgical replacement is at increased risk. However, TAVI-induced effects on myocardial efficiency are unknown. We aimed to investigate changes in LV mechano-energetic pre-/post-TAVI and their prognostic impact. METHODS: A total of 46 patients (25 males) received transesophageal and simultaneous radial pressure plus transaortic gradient monitoring before/immediately after prosthesis deployment. Efficiency was computed as external work/potential energy, as derived from LV pressure-volume plots; myocardial oxygen consumption (MVO2) was estimated as PWImod, i.e. a noninvasively validated alternative for MVO2 estimation. RESULTS: TAVI was successful in all patients, peak transaortic gradient decreasing - 40 ± 20 mmHg (p < 0.001). Efficiency improved post-TAVI (+ 0.6 ± 0.12; p = 0.004), with a concomitant PWImod reduction (- 16 ± 31%; p < 0.001). When contextualized to fixed PWImod value (5 ml/min/100 g), efficiency significantly affected survival (p = 0.029). Over 1026 ± 450-day follow-up, a change in efficiency pre-/post-TAVI ≤ 0.021 (median of the difference) predicted more deaths from any cause (30%) as compared with a change > 0.021 (17%), particularly in those patients with a pre-TAVI mean high-gradient (HG ≥ 40 mmHg) phenotype (p < 0.05). In particular, HG patients exhibited the lowest efficiency/PWImod ratio pre-/post-TAVI (p = 0.048), relative to the other aortic stenosis patients, suggestive of an unfavourable matching between cardiac function and metabolic demand, which foreshortens some intrinsic damaged muscle condition in these patients. CONCLUSION: LV mechanical efficiency improves immediately post-TAVI, notwithstanding an inhomogeneous mechano-energetic matching among the aortic stenosis patients, which can impact negatively on their long-term prognosis, particularly in those with the HG phenotype.

Prevalence of undiagnosed chronic thromboembolic pulmonary hypertension after pulmonary embolism.

Chronic thromboembolic pulmonary hypertension is associated with adverse prognosis. Early diagnosis is important to better identify patients who would benefit from a well established therapeutic strategy. The purpose of our study was to evaluate long-term incidence of undiagnosed chronic thromboembolic pulmonary hypertension after acute pulmonary embolism and the utility of a long-term follow-up including an echocardiographic-based screening programme to early detect this disease. We evaluated retrospectively 282 patients discharged from the 'Maggiore della Carità' Hospital, Università del Piemonte Orientale, Novara, Italy, with diagnosis of acute pulmonary embolism between November 2006 and October 2009. One hundred and eleven patients underwent a clinical late echocardiographic screening programme after the acute event. Patients with suspected pulmonary hypertension based on echocardiographic evidence of systolic pulmonary artery pressure of at least 40  mmHg underwent complete work-up for chronic thromboembolic pulmonary hypertension assessment, including ventilation-perfusion lung scintigraphy and right heart catheterization. One hundred and eleven patients were included in the study. Pulmonary hypertension was suspected in 15 patients; five patients had chronic thromboembolic pulmonary hypertension confirmed by ventilation-perfusion lung scintigraphy, right heart catheterization and pulmonary angiography. Two patients with clinical class functionally advanced underwent surgical pulmonary endarterectomy and two asymptomatic patients underwent medical treatment. The prevalence of undiagnosed chronic thromboembolic pulmonary hypertension was 4.5%. Chronic thromboembolic pulmonary hypertension is a serious disease with a poor prognosis if not treated early. Surgical treatment is decisive. After surgery, the majority of patients have a substantial improvement in their functional status and in haemodynamic variables. Many patients are asymptomatic. Implementation of screening programmes may be helpful for an early diagnosis and early proper therapy.

Silent double aortic arch coincidentally found during cardiac catheterization in elderly man.

We describe a case of an elderly man known for coronary artery disease (previous bypass surgery) hospitalized for ischemia in inferior wall. Since the operation, the patient underwent coronary angiographies. Due to the impossibility of selective engagement of left subclavian artery from femoral access, LIMA was always visualized through a right radial approach. Despite the suspicious of abnormal origin of left subclavian artery, aortic angiography was never performed. During the third angiography, the double aortic arch was coincidentally visualized by using a left Amplatz catheter. The diagnosis was confirmed by 64-slice computed tomography scan.

Cardiac dyssynchrony quantitated by time-to-peak or temporal uniformity of strain at longitudinal, circumferential, and radial level: implications for resynchronization therapy.

BACKGROUND: The standard deviation of time to peak strain (TPS-SD) has been proposed as an index of left ventricular (LV) dyssynchrony in patients to be resynchronized. However, TPS-SD is sensitive to noise, and the influence of outliers on TPS-SD is also relevant. Alternatively, dyssynchrony can be indexed by temporal uniformity of strain (TUS), whereby a time plot of regional strains, arranged for LV location, is subjected to Fourier analysis. If segments shorten simultaneously (synchronously), the plot appears as a straight line, with power only in the zero-order Fourier term, whereas regionally clustered dyssynchrony generates an undulating plot with higher power in the first-order term. TUS index reflects zero-order relative to first-order plus zero-order power. METHODS: In this study, TUS and TPS-SD were computed in 68 patients (QRS duration >/= 120 ms; ejection fraction