[Show abstract][Hide abstract] ABSTRACT: The current practice of physical diagnosis is dependent on physician skills and biases, inductive reasoning, and time efficiency. Although the clinical utility of echocardiography is well known, few data exist on how to integrate 2-dimensional screening "quick-look" ultrasound applications into a novel, modernized cardiac physical examination. We discuss the evidence basis behind ultrasound "signs" pertinent to the cardiovascular system and elemental in synthesis of bedside diagnoses and propose the application of a brief cardiac limited ultrasound examination based on these signs. An ultrasound-augmented cardiac physical examination can be taught in traditional medical education and has the potential to improve bedside diagnosis and patient care.
Full-text · Article · Aug 2015 · Journal of ultrasound in medicine: official journal of the American Institute of Ultrasound in Medicine
[Show abstract][Hide abstract] ABSTRACT: Allogeneic mesenchymal precursor cells (MPCs) have been effective in large animal models of ischemic and non-ischemic heart failure (HF).
To evaluate the feasibility and safety of 3 doses (25, 75, or 150 million [M] cells) of immunoselected allogeneic MPCs in chronic HF patients in a phase 2 trial.
We sequentially allocated 60 patients to a dosing cohort (20 per dose-group) and randomized them to transendocardial MPC injections (n=15) or mock procedures (n=5). The primary objective was safety, including antibody testing. Secondary efficacy endpoints included major adverse cardiac events (MACE; cardiac death, myocardial infarction, or revascularization), left ventricular imaging, and other clinical-event surrogates. Safety and MACE were evaluated for up to 3 years. MPC injections were feasible and safe. Adverse events were similar across groups. No clinically symptomatic immune responses were noted. MACE was seen in 15 patients: 10/45 (22%) MPC-treated and 5/15 (33%) control patients. We found no differences between MPC-treated and control patients in survival probability, MACE-free probability, and all-cause mortality. We conducted a post-hoc analysis of HF-related MACE (HF hospitalization, successfully resuscitated cardiac death, or cardiac death); events were significantly reduced in the 150M group (0/15) versus control (5/15;33%), 25M (3/15;20%), and 75M (6/15;40%); the 150M group differed significantly from all groups according to Kaplan-Meyer statistics over 3 years (P=0.025 for 150M vs control).
Transendocardial injections of allogeneic MPCs were feasible and safe in chronic HF patients. High-dose allogeneic MPCs may provide benefits in this population.
No preview · Article · Jul 2015 · Circulation Research
[Show abstract][Hide abstract] ABSTRACT: Hepatocyte growth factor (HGF) has been shown to have anti-fibrotic, pro-angiogenic, and cardioprotective effects; however, it is highly unstable and expensive to manufacture, hindering its clinical translation. Recently, a HGF fragment (HGF-f), an alternative c-MET agonist, was engineered to possess increased stability and recombinant expression yields. In this study, we assessed the potential of HGF-f, delivered in an extracellular matrix (ECM)-derived hydrogel, as a potential treatment for myocardial infarction (MI). HGF-f protected cardiomyocytes from serum-starvation and induced down-regulation of fibrotic markers in whole cardiac cell isolate compared to the untreated control. The ECM hydrogel prolonged release of HGF-f compared to collagen gels, and in vivo delivery of HGF-f from ECM hydrogels mitigated negative left ventricular (LV) remodeling, improved fractional area change (FAC), and increased arteriole density in a rat myocardial infarction model. These results indicate that HGF-f may be a viable alternative to using recombinant HGF, and that an ECM hydrogel can be employed to increase growth factor retention and efficacy.
[Show abstract][Hide abstract] ABSTRACT: The goal of this study is to validate a new, continuous, noninvasive stroke volume (SV) method, known as transbrachial electrical bioimpedance velocimetry (TBEV). TBEV SV was compared to SV obtained by cardiac magnetic resonance imaging (cMRI) in normal humans devoid of clinically apparent heart disease. Thirty-two (32) volunteers were enrolled in the study. Each subject was evaluated by echocardiography to assure that no aortic or mitral valve disease was present. Subsequently, each subject underwent electrical interrogation of the brachial artery by means of a high frequency, low amplitude alternating current. A first TBEV SV estimate was obtained. Immediately after the initial TBEV study, subjects underwent cMRI, using steady-state precession imaging to obtain a volumetric estimate of SV. Following cMRI, the TBEV SV study was repeated. Comparing the cMRI-derived SV to that of TBEV, the two TBEV estimates were averaged and compared to the cMRI standard. CO was computed as the product of SV and heart rate. Statistical methods consisted of Bland-Altman and linear regression analysis. TBEV SV and CO estimates were obtained in 30 of the 32 subjects enrolled. Bland-Altman analysis of pre- and post-cMRI TBEV SV showed a mean bias of 2.87 % (2.05 mL), precision of 13.59 % (11.99 mL) and 95 % limits of agreement (LOA) of +29.51 % (25.55 mL) and -23.77 % (-21.45 mL). Regression analysis for pre- and post-cMRI TBEV SV values yielded y = 0.76x + 25.1 and r(2) = 0.71 (r = 0.84). Bland-Altman analysis comparing cMRI SV with averaged TBEV SV showed a mean bias of -1.56 % (-1.53 mL), precision of 13.47 % (12.84 mL), 95 % LOA of +24.85 % (+23.64 mL) and -27.97 % (-26.7 mL) and percent error = 26.2 %. For correlation analysis, the regression equation was y = 0.82x + 19.1 and correlation coefficient r(2) = 0.61 (r = 0.78). Bland-Altman analysis of averaged pre- and post-cMRI TBEV CO versus cMRI CO yielded a mean bias of 5.01 % (0.32 L min(-1)), precision of 12.85 % (0.77 L min(-1)), 95 % LOA of +30.20 % (+0.1.83 L min(-1)) and -20.7 % (-1.19 L min(-1)) and percent error = 24.8 %. Regression analysis yielded y = 0.92x + 0.78, correlation coefficient r(2) = 0.74 (r = 0.86). TBEV is a novel, noninvasive method, which provides satisfactory estimates of SV and CO in normal humans.
Preview · Article · Feb 2015 · Journal of Clinical Monitoring and Computing
[Show abstract][Hide abstract] ABSTRACT: Background
Right ventricular (RV) function is significantly impaired in patients with chronic thromboembolic pulmonary hypertension (CTEPH). Two-dimensional speckle tracking RV strain and strain rate are novel methods to assess regional RV systolic function in CTEPH patients before and after pulmonary thromboendarterectomy (PTE). Our goal was to (1) assess baseline longitudinal strain and strain rate of the basal RV free wall in CTEPH and (2) measure early changes in RV strain and strain rate after PTE.Methods
We performed echocardiography on 30 consecutive patients with CTEPH referred for PTE with adequate pre- and post-PTE strain imaging. Strain and strain rate were assessed 6.4 ± 4.5 days before and 9.1 ± 3.9 after PTE.ResultsBasal RV free wall strain and time to peak strain—but not basal RV strain rate and time to peak strain rate—changed significantly after PTE. Unexpectedly, basal RV strain became less negative, from −24.3% to −18.9% after PTE (P = 0.005). Time to peak strain decreased from 356 to 287 msec after PTE (P < 0.001). Preoperatively, RV strain correlated with pulmonary vascular resistance (PVR) and mean pulmonary artery pressure (mPAP) but this relationship was not evident postoperatively. Furthermore, the change in RV strain did not correlate with the change in mPAP or PVR.Conclusions
In patients with CTEPH, RV basal strain paradoxically became less negative (i.e., relative systolic shortening decreased) following PTE. This change in RV strain could be due to intraoperative RV ischemia and/or postoperative stunning. Thus, RV basal strain cannot be used as a surrogate marker for surgical success early after PTE.
[Show abstract][Hide abstract] ABSTRACT: Background
Impaired left ventricular diastolic filling is common in chronic thromboembolic pulmonary hypertension (CTEPH), and recent studies support left ventricular underfilling as a cause. To investigate this further, we assessed left atrial volume index (LAVI) in patients with CTEPH before and after pulmonary thromboendarterectomy (PTE).
Forty-eight consecutive CTEPH patients had pre- & post-PTE echocardiograms and right heart catheterizations. Parameters included mean pulmonary artery pressure (mPAP), pulmonary vascular resistance (PVR), cardiac index, LAVI, & mitral E/A ratio. Echocardiograms were performed 6 ± 3 days pre-PTE and 10 ± 4 days post-PTE. Regression analyses compared pre- and post-PTE LAVI with other parameters.
Pre-op LAVI (mean 19.0 ± 7 mL/m2) correlated significantly with pre-op PVR (R = -0.45, p = 0.001), mPAP (R = -0.28, p = 0.05) and cardiac index (R = 0.38, p = 0.006). Post-PTE, LAVI increased by 18% to 22.4 ± 7 mL/m2 (p = 0.003). This change correlated with change in PVR (765 to 311 dyne-s/cm5, p = 0.01), cardiac index (2.6 to 3.2 L/min/m2, p = 0.02), and E/A (.95 to 1.44, p = 0.002).
In CTEPH, smaller LAVI is associated with lower cardiac output, higher mPAP, and higher PVR. LAVI increases by ~20% after PTE, and this change correlates with changes in PVR and mitral E/A. The rapid increase in LAVI supports the concept that left ventricular diastolic impairment and low E/A pre-PTE are due to left heart underfilling rather than inherent left ventricular diastolic dysfunction.
Full-text · Article · Aug 2014 · Cardiovascular Ultrasound
[Show abstract][Hide abstract] ABSTRACT: Impaired left ventricular diastolic filling is common in chronic thromboembolic pulmonary hypertension (CTEPH), and recent studies support left ventricular underfilling as a cause. To investigate this further, we assessed left atrial volume index (LAVI) in patients with CTEPH before and after pulmonary thromboendarterectomy (PTE).
Full-text · Article · Apr 2014 · Journal of the American College of Cardiology
[Show abstract][Hide abstract] ABSTRACT: Objective
To assess the safety and efficacy of extracorporeal shockwave myocardial revascularization (ESMR) therapy in treating patients with refractory angina pectoris.
Patients and Methods
A single-arm multicenter prospective trial to assess safety and efficacy of the ESMR therapy in patients with refractory angina (class III/IV angina) was performed. Screening exercise treadmill tests and pharmacological single-photon emission computed tomography (SPECT) were performed for all patients to assess exercise capacity and ischemic burden. Patients were treated with 9 sessions of ESMR to ischemic areas over 9 weeks. Efficacy end points were exercise capacity by using treadmill test as well as ischemic burden on pharmacological SPECT at 4 months after the last ESMR treatment. Safety measures included electrocardiography, echocardiography, troponin, creatine kinase, and brain natriuretic peptide testing, and pain questionnaires.
Fifteen patients with medically refractory angina and no revascularization options were enrolled. There was a statistically significant mean increase of 122.3±156.9 seconds (38% increase compared with baseline; P=.01) in exercise treadmill time from baseline (319.8±157.2 seconds) to last follow-up after the ESMR treatment (422.1±183.3 seconds). There was no improvement in the summed stress perfusion scores after pharmacologically induced stress SPECT at 4 months after the last ESMR treatment in comparison to that at screening; however, SPECT summed stress score revealed that untreated areas had greater progression in ischemic burden vs treated areas (3.69±6.2 vs 0.31±4.5; P=.03). There was no significant change in the mean summed echo score from baseline to posttreatment (0.4±5.1; P=.70). The ESMR therapy was performed safely without any adverse events in electrocardiography, echocardiography, troponins, creatine kinase, or brain natriuretic peptide. Pain during the ESMR treatment was minimal (a score of 0.5±1.2 to 1.1±1.2 out of 10).
In this multicenter feasibility study, ESMR seems to be a safe and efficacious treatment for patients with refractory angina pectoris. However, larger sham-controlled trials will be required to confirm these findings.
No preview · Article · Mar 2014 · Mayo Clinic Proceedings
[Show abstract][Hide abstract] ABSTRACT: Ultrasound contrast agent safety has received recent attention based on reports of associated serious adverse events. The US Food and Drug Administration requested this postmarketing study of the effects of Optison on pulmonary hemodynamics. The aim of this study was to compare Optison and a placebo for effects on pulmonary artery systolic pressure (PASP) and pulmonary vascular resistance (PVR) during right-sided cardiac catheterization. This was a single-blind, crossover, placebo-controlled, multicenter study of Optison in subjects referred for clinically indicated cardiac catheterization. Based on screening echocardiographic PASP, subjects were assigned to 1 of 2 strata (1 = normal PASP [≤35 mm Hg] and 2 = elevated PASP [>35 mm Hg]), in which they were randomized to treatment arm A (intravenous 0.5 ml Optison and then intravenous 0.5 ml placebo [5% dextrose] 15 minutes later) or arm B (intravenous 0.5 ml placebo [5% dextrose] and then 0.5 ml Optison 15 minutes later). Baseline pulmonary hemodynamics were obtained within 60 minutes before the first injection and 2, 6, and 10 minutes after each injection. Thirty patients each received their assigned treatments. There were no clinically relevant increases from baseline in mean PASP or PVR (Wood units) in either stratum alone or the combined strata. There were no serious adverse events. In conclusion, there is no change in PASP or PVR after intravenous injection of Optison at a clinically relevant dose in patients with normal or elevated baseline PASP.
Full-text · Article · Sep 2013 · The American journal of cardiology