A technical and data analytic approach to pressure-volume loops over numerous cardiac cycles

Cardiac pressure-volume (PV) loop analysis is the reference standard for studying the cardiovascular implications of clinical perturbations (eg, heart failure, aortic occlusion, hypovolemia) and is a benchmark for comparisons with noninvasive alternatives (eg, ultrasound, magnetic resonance imaging). Historically, most PV loop analyses were of individual cardiac cycles for which the options to analyze PV loops using off-the-shelf software were limited, and home-grown analysis software often lacked peer review or code-sharing. Our aim was to describe a start-to-finish implementation of PV loops for determination of hemodynamic parameters in swine, to provide technical advice for vascular access and proceduralization, and to describe data capture, curation, preprocessing, and analysis of raw PV time data. We have provided a novel data analytic method to programmatically analyze raw PV loop data beyond single cardiac cycles and real, raw swine PV loop data and the accompanying MATLAB (MathWorks, Inc, Natick, Mass) code as an example of how to process and analyze raw data directly.

Favorable changes of left ventricular function in the circumferential direction following transcatheter atrial septal defect closure: a strain imaging study

To clarify the impact on left ventricular (LV) function of percutaneous atrial septal defect (ASD) closure in adult patients. Echocardiograms of 46 patients (52 ± 18 years) who underwent ASD closure with a significant left-to-right shunt obtained before and 1 month after the procedure were retrospectively analyzed. Functional parameters were obtained by 2-dimensional speckle-tracking imaging. Global longitudinal strain and strain rate at early diastole (SRe) was calculated from the three standard apical views, while circumferential and radial parameters were calculated from basal, middle, and apical LV short-axis views. Along with a diminished right ventricular (RV) volume, the LV volume and ejection fraction increased (end-diastolic volume: 61 ± 12 to 76 ± 15 mL, p < 0.001; and 63% ± 4 to 64% ± 4% p = 0.03; respectively). Both global strain and SRe was augmented only in the circumferential direction (- 16.2% ± 2.9% to - 19.8% ± 2.8%; and 1.07 ± 0.29 to 1.34 ± 0.28 s^-1, both p < 0.001). Augmentation of circumferential SRe correlated with both the changes in and the pre-procedural value of diastolic LV eccentricity index (r = - 0.57, p < 0.001; and r = 0.37, p = 0.01; respectively), a morphological parameter of RV volume overload. Following ASD closure in adults, both LV systolic and diastolic function could favorably change in the circumferential direction, and the degree of diastolic functional change is associated with RV volume overload, i.e., severity of ventricular interdependence.

Assessing Right Ventricular Function in the Perioperative Setting, Part II: What About Catheters?

An-depth assessment of right ventricular function is important in a many perioperative settings. After exploring 2-dimensional echo-based evaluation, other proposed monitoring modalities are discussed. Pressure-based methods of right ventricular appraisal is discussed. Flow-based assessment is reviewed. An overview of the state of current right ventricular 3-dimensional echocardiography and its potential to construct clinical pressure-volume loops in conjunction with pressure measurements is provided. An overview of right ventricular assessment modalities that do not rely on 2-dimensional echocardiography is discussed. Tailored selection of monitoring modalities can be of great benefit for the perioperative physician. Integrating modalities offers optimal estimations of right ventricular function.

Left ventricular function in adult patients with atrial septal defect: implication for development of heart failure after transcatheter closure

Despite advances in device closure for atrial septal defect (ASD), post-closure heart failure observed in adult patients remains a clinical problem. Although right heart volume overload is the fundamental pathophysiology in ASD, the post-closure heart failure characterized by acute pulmonary congestion is likely because of age-related left ventricular diastolic dysfunction, which is manifested by acute volume loading with ASD closure. Aging also appears to play important roles in the pathophysiology of heart failure through several mechanisms other than diastolic dysfunction, including ventricular systolic and vascular stiffening and increased incidence of comorbidities that significantly affect cardiovascular function. Recent studies suggested that accurate assessment of preclosure diastolic function, such as test ASD occlusion, may help identify high-risk patients for post-closure heart failure. Anti-heart failure therapy before device closure or the use of fenestrated device appears to be effective in preventing post-closure heart failure in the high-risk patients. However, the long-term outcome of such patients remains to be elucidated. Future studies are warranted to construct an algorithm to identify and treat patients at high risk for heart failure after device closure of ASD.