Contractility In Patients Research Articles

Association of prediabetes with impaired left atrial contractility in patients with never-treated hypertension.

Prediabetes defined by HbA1c 5.7-6.4 has been shown to be associated with left ventricular (LV) hypertrophy and diastolic dysfunction in hypertensive patients. We hypothesized HbA1c prediabetes may be related to the alterations of LA contractility or volume in nondiabetic hypertension. Nondiabetic individuals on sinus rhythm were enrolled; 107 patients with never-treated hypertension, 134 patients with treated hypertension, and 71 normotensive subjects. Participants were classified as normal glucose tolerance (NGT, HbA1c<5.7), prediabetes (HbA1c 5.7-6.4) according to the ADA criteria. They underwent echocardiography to measure left atrial (LA) phasic volumes and functions, as well as mitral E/e' and mitral e'. In nondiabetic patients with never-treated hypertension, prediabetes saw lower LA total emptying fraction (53.7 ± 8.2 vs. 48.3 ± 9.9*) and mitral e' (7.38 ± 2.18 vs. 6.17 ± 1.50*) than NGT, implicating that the association of prediabetes with reduced LA contractility and LV stiffness. On the other hand, in nondiabetic patients with treated hypertension, prediabetes saw higher maximum LA volume/BSA (29.7 ± 7.1 vs. 32.9 ± 6.2* ml/mm2) and mitral E/e' (10.72 ± 3.08 vs. 12.37 ± 3.35*) than NGT, suggesting the relationship of prediabetes with increased LA preload. Prediabetes may be involved in the progression of LA structural and functional alterations in nondiabetic hypertensive patients.

Prediction of detrusor underactivity based on non-invasive functional tests and clinical data in patients with symptoms of bladder outlet obstruction.

Detrusor underactivity (DU) is a common but relatively under-researched bladder dysfunction. Recently, there has been renewed interest in this topic. The aim of the study was to develop a decision-making algorithm to predict the impaired detrusor contractility in patients with LUTS (lower urinary tract symptoms). A retrospective analysis covered 96 consecutive patients (aged 63 ± 8 years) treated pharmacologically for 50 ± 37 months due to LUTS (persisting for 64 ± 41 months). Functional tests included uroflowmetry and flow cystometry. Weakened detrusor functioning was detected in 58 (60.4%) patients. Decision-making algorithm that included uroflowmetry, flow cystometry and clinical data, was showed to allow to diagnose impaired detrusor function with accuracy of 73% (95% CI - confidence interval: 61-83%) and specificity of 76% (95% CI: 54-90%). The positive predictive value of the classification tree graph is equal to 90% (95% CI: 78 -96%) and the negative predictive value is 50% (95% CI: 34-66%). The weakened detrusor function was more frequent in patients with: time to reach maximum flow rate higher than 13.5 s; time to reach maximum flow rate lower than 13.5 s and mean flow ratio higher than 4.5 ml/s, but time of flow longer than 44.5 s; time to reach maximum flow rate lower than 13.5 s and mean flow ratio lower than 4.5 ml/s, but time of flow longer than 52.5 s. The results of the uroflowmetry can be used to predict the impaired detrusor contractility in patients with LUTS.

Sol ventrikül fonksiyonları bozulmuş, ejeksiyon fraksiyonu %40’ın altında olan, koroner arter by-pass greft operasyonu yapılacak hastalara verilen levosimendan tedavisinin, kardiyoprotektif etkinliğinin postoperatif olarak değerlendirilmesi

The purpose of this study is to demonstrate the postoperative cardioprotective efficacy of preoperative levosimendan treatment in patients with impaired left ventricular function undergoing coronary by-pass surgery. Materyal and Method: This study was performed prospectively between November 2008 and September 2009 in Eskişehir Osmangazi Univercity Department of Cardiovascular Surgery. Twenty patients with coronary artery disease (CAD) between the ages of 48-78 and ejection fraction (EF) below 40% were included in the study. levosimendan was given to the first group preoperatively(experimental group). Group 2 was the control group. Coronary artery bypass graft (CABG) surgery was performed in all of them. One group received additional levosimendan infusion, preoperatively. Age, comorbidity, cardiopulmonary by-pass (CPB) time, cross clamp (CC) time, patient vessel number, anastomosis number, extubation times, intensive care stay and hospital stay were recorded. Preoperative, postoperative 1st day and postoperative 7th day nt-proBNP values and preoperative and postoperative 15th day ejection fraction (EF) values with echocardiography (ECHO) were measured. The cardioprotective efficacy of the drug was evaluated by comparing the data of the control group and the experimental group. Results: No statistically significant difference was found between the two groups in terms of CPB time, CC time, age, comorbidity, number of sick vessels, number of anastomosis, extubation time, length of stay in intensive care and hospital stay. (P&amp;gt; 0.05). There was no significant difference between the groups in preoperative EF values (P&amp;gt; 0.05). The mean values of EF measurements on the postoperative 15th day were calculated as 39% in the experimental group and 40% in the control group. The increase in EF values was greater in the experimental group. This increase was found to be more significant in the experimental group (P = 0.008). There was a significant difference between the groups in preoperative and postoperative 1st day n-tproBNP values (P &amp;lt;0.05). A significant increase was observed in nt-proBNP values in the groups until the 7th postoperative day. (P &amp;lt;0.001). Although this increase was statistically significant in both groups, it was observed that the increase in the control group was higher. After the nt-proBNP measurements on the postoperative 7th day, there was no significant difference between the two groups (P&amp;gt; 0.05). Conclusion: As a result of this study, it was determined that levosimendan has a positive effect on myocardial protection and contractility in patients with low EF in CABG surgery. Keywords: Levosimendan; coroner by-pass surgery; left ventricle dyusfunction.

Modulation of cardiac contractility in patients with chronic heart failure and atrial fibrillation

to evaluate the effectiveness of cardiac contractility modulation (MSS) in patients with chronic heart failure (CHF) and atrial fibrillation (AF). The following studies were performed in 40 patients with CHF and AF before implantation of the MSS device and after 2 and 6 months of follow-up: 12-channel ECG, transthoracic EchoCG, 6-minute walk test, determination of the level of Pro-natriuretic N-terminal peptide (NT-proBNP), daily ECG monitoring, and a questionnaire based on the Minnesota quality of life questionnaire for patients with CHF (MHFLQ). All patients received long-term optimal drug therapy for CHF before surgery. The results obtained indicate a statistically significant positive effect of the use of MSS in patients with CHF and AF on LV FV, the functional class of CHF, and levels of NT-proBNP regardless of the etiology of CHF. The use of MSS may be promising for the treatment of heart failure in patients with CHF and AF.

970 - Assessment of bladder contractility in patients with benign prostate hyperplasia using invasive and non invasive urodynamics

970 - Assessment of bladder contractility in patients with benign prostate hyperplasia using invasive and non invasive urodynamics

Characterizing the proximal esophageal segment in patients with symptoms of esophageal dysmotility.

Proximal esophageal striated muscle contractility may be abnormal in patients with esophageal symptoms, but is not assessed in the Chicago Classification (CC) v3.0. We aimed to (a) determine the prevalence of abnormal proximal esophageal contractility in patients with esophageal symptoms; (b) compare proximal esophageal contractility in patients with different esophageal motility disorders; (c) assess the association of abnormal proximal esophageal contractility with esophageal symptoms. Patients undergoing high-resolution esophageal manometry (HREM) from 7/2019 to 11/2019 and healthy volunteers (HVs) were studied. Measurements of the proximal esophageal segment included the vigor of contractility of the proximal esophagus (proximal contractile integral/PCI). Patients rated gastrointestinal symptoms' severity. HREM was performed on 221 patients (63.8% females, mean age 57.1±1.1years) and 19 HVs. Mean PCI in HVs was 299.5±30.6 (95% CI 32.3-566.7mmHg. s. cm). Of all patients, 61 (27.6%) had abnormal PCI. HVs and patients with different esophageal motility disorders had significantly different PCI (P<.01). Type 1 achalasia patients had weaker PCI than patients with absent contractility (P=.02). Patients with abnormal PCI had more severe dysphagia (P=.02), nausea (P=.03), vomiting (P=.03), and lower bolus clearance (P<.01) than patients with normal PCI. Abnormal PCI was found in a fourth of patients with esophageal symptoms. PCI may be useful to distinguish some esophageal motility disorders. Patients with abnormal PCI had a higher severity of some upper gastrointestinal symptoms than patients with normal PCI. Assessing the proximal esophageal segment on HREM may be useful in characterizing patients with esophageal symptoms.

State of central hemodynamics and myocardial contractility in vibration disease

The article describes the peculiarities of Central hemodynamics and myocardial contractility in patients with vibration disease, various forms and degrees of severity with the help of echocardiography of the Department of pathology of the regional center of occupational pathology of SBME "Samara mediko-a sanitary part of № 5 of Kirov district". It was found that patients with vibration disease are characterized by the formation of a phase syndrome of myocardial hyperdynamics and a hyperkinetic variant of Central hemodynamics, while hemodynamic changes depend on the form of vibration disease, the severity of the disease, and the length of work in contact with vibration.

Reduced Coronary Flow Reserve Is Associated with Impaired Ventricular-vascular Interaction in Patients with Obstructive Sleep Apnea.

Background and ObjectivesObstructive sleep apnea (OSA) is associated with cardiac and arterial damage and adverse cardiovascular outcomes. We aimed to determine whether coronary flow reserve (CFR), which represents microvascular dysfunction, might be associated with the ventricular-vascular coupling index (VVI), which represents the afterload-adjusted contractility in patients with OSA.MethodsWe enrolled 281 patients (257 males; mean age, 43±11 years) with newly diagnosed OSA. Transthoracic echocardiography was performed, and adenosine-associated CFR was measured in the left anterior descending coronary artery. We evaluated the differences between the patients with normal CFR ≥2.5 and reduced CFR <2.5. VVI was calculated using the effective arterial elastance (Ea) and left ventricular (LV) end-systolic elastance (Ees) as follows: 10×Ea/Ees.ResultsThe normal CFR group (n=214) showed increased Ees (7.28±2.31 vs. 8.14±2.33 mmHg/mL, p=0.016) and preserved VVI (3.17±1.53 vs. 2.78±1.20, p=0.044) compared with the reduced CFR group (n=67). There were no differences in LV dimension, LV ejection fraction, left atrial-volume index, E/e′, left atrial strain and LV global longitudinal strain between the 2 groups (all p>0.05). CFR was significantly correlated to Ees (r=0.139; p=0.023) and VVI (r=−0.137; p=0.025).ConclusionsReduced CFR is associated with decreased Ees and impaired VVI in OSA patients. It suggests the necessity of more intensive observation in OSA patients with reduced CFR to improve cardiovascular outcomes.

429 Right ventricular longitudinal and radial fiber contractility in patients undergoing mitral valve surgery: a PREPARE-MVR substudy

Abstract Severe mitral regurgitation results in significant hemodynamic demands of not only the left, but the right ventricle (RV) as well. Increased pulmonary pressures and consequential pressure overload of the RV induces complex remodeling, which can be partially restored by mitral valve repair/replacement (MVR). MVR is associated with marked changes of RV deformation, however, the clinical significance of these changes is not well estabilished. The PREPARE-MVR study (PRediction of Early PostoperAtive Right vEntricular failure in Mitral Valve Replacement/Repair patients) aims to determine parameters, which may predict the perioperative risk of acute RV failure. In this current substudy, our aim was to determine the changes of RV global, longitudinal and radial fiber contractility before and following MVR. Our study group consisted of 27 MVR patients (mean age: 64 ± 12 years, m/f: 19/8). Transthoracic 3D echocardiography was performed before the operation and following intensive care unit discharge. 3D beutel model of the RV was created and RV end-diastolic volume index (EDVi) among with RV ejection fraction (RVEF) were calculated using commercially available software. For in-depth analysis of RV mechanics, we have decomposed the motion of the RV using our custom software (ReVISION) to determine longitudinal (LEF) and radial ejection fraction (REF). Right heart catheterization was also performed before MVR and 24 hours after MVR as well to measure pulmonary arterial mean systolic pressure (mPAP), pulmonary arterial wedge pressure (PAWP) and RV stroke work index (RVSWi). Using the aforementioned parameters, we have calculated RV longitudinal (longRVSWi) and RV radial stroke work index (radRVSWi), which represent RV longitudinal and radial fiber contractility. RV morphology did not change significantly according to RVEDVi (preop vs. postop: 71 ± 17 vs. 72 ± 20 mL/m², p = NS). RVEF slightly decreased after MVR (50 ± 6 vs. 48 ± 7 %, p &amp;lt; 0.05), however, RV motion pattern markedly changed. Postoperative LEF was significantly lower compared to preoperative values (25 ± 6 vs. 16 ± 6%, p &amp;lt; 0.0001), among with an increase in REF (21 ± 7 vs. 27 ± 7%, p &amp;lt; 0.01). As expected, mPAP and PAWP decreased in response to MVR (mPAP: 30 ± 10 vs. 25 ± 7 mmHg; PAWP: 19 ± 7 vs. 13 ± 3 mmHg, both p &amp;lt; 0.01). Global RV contractility decreased after surgery (RVSWi: 603 ± 355 vs. 474 ± 251 mmHg*mL/m², p &amp;lt; 0.05). While RV longitudinal contractility also significantly reduced (longRVSWi: 289 ± 179 vs. 166 ± 122 mmHg*mL/m², p &amp;lt; 0.001), radial contractility was maintained following MVR (radRVSWi: 240 ± 141 vs. 261 ± 144 mmHg*mL/m², p = NS). MVR is associated with marked changes of RV function and hemodynamics. RV longitudinal and radial contractility have distinct response to surgery, which may be important in postoperative patient management. The PREPARE-MVR study aims to examine the role of preoperative RV mechanics in clinical outcome.

Острое влияние активной правожелудочковой стимуляции на степень трикуспидальной регургитации и соркатимости правого желудочка у пациентов с синдромом слабости синусного узла, независимо от явления механической интерференции

Острое влияние активной правожелудочковой стимуляции на степень трикуспидальной регургитации и соркатимости правого желудочка у пациентов с синдромом слабости синусного узла, независимо от явления механической интерференции

Change of Detrusor Contractility in Patients with and without Bladder Outlet Obstruction at Ten or More Years of follow-up

To analyze the change of detrusor contractility by investigating urodynamic characteristics with long term follow-up. This study retrospectively reviewed 166 lower urinary tract symptoms patients without bladder outlet obstruction (BOO) and 63 patients with BOO who underwent repeated urodynamic studies at the first time and more than 10 years later. The urodynamic parameters, bladder contractility index (BCI), and BOO index (BOOI) were compared before and after. As time goes by, detrusor pressure at maximum flow rate (PdetQmax) significantly decreased and post-void residual (PVR) volume significantly increased in both men and women. Full sensation, urge sensation, voided volume, and BCI significantly decreased. We also compared men with and without BOO, PdetQmax, maximum flow rate (Qmax), voided volume, and BCI all significantly decreased in both groups without difference. PVR increased greater in men with BOO after >10 years significantly (p = 0.036). Women with detrusor overactivity (DO) under antimuscarinic showed no significant BCI change compared to patients without DO (p = 0.228). Detrusor contractility decreases in men and women after >10 years of follow-up. However, this finding suggests that patients with BOO or DO under adequate medical treatment, detrusor contractility is not aggravated over 10 or more years of follow-up.

Ultrasound guidance increases diagnostic yield of needle EMG in plegic muscle

ObjectivesTo increase the specificity of motor unit potential (MUPs) detection by using ultrasound guided electromyography (USG-EMG) in patients with muscle plegia due to traumatic nerve lesions. MethodsForty-six patients with recent nerve trauma underwent baseline standard EMG (ST-EMG) evaluation with evidence of absent MUPs. In 41 of them, ST-EMG was repeated after 2–3 months (T1) and the patients were accordingly divided in two groups: ST-EMG+ (if MUPs were detected) or ST-EMG- (MUPs not detected). Then, ST-EMG- patients underwent muscle ultrasound evaluation (M-US) and, if isles of muscular contractility were found, they also had USG-EMG. The same protocol was repeated 4–6 months after baseline (T2). ResultsAt T1, 22/41 patients were ST-EMG+. While 19/41 were ST-EMG-; 9 of these patients had M-US consistent with residual muscular activity, for that reasons underwent USG-EMG with 7 of 9 demonstrating MUPs (at T2 all of these 7 patients resulted ST-EMG). In the other 2 patients, we found no MUPs at T1 but they became ST-EMG+ or USG-EMG positive at T2. The remaining 10 ST-EMG- patients had no EMG or US evidence of muscle contraction at T1, but at T2 2 of 10 became ST-EMG+ and 2 had USG-EMG showing MUPs. In the remaining 6 patients still M-US negative at T2, complete denervation was diagnosed. Concerning the 22 patients who were ST-EMG+ at T1, all but one showed increase of MUPs at T2. ConclusionsIn this study, we demonstrated the utility of US guidance when performing EMG evaluation in locating isles of muscular contractility in patients who have no detectable MUPs on EMG after nerve trauma. SignificanceUSG-EMG significantly increases the specificity of needle EMG allowing earlier detection of MUPs.

Computational quantification of patient-specific changes in ventricular dynamics associated with pulmonary hypertension.

Pulmonary arterial hypertension (PAH) causes an increase in the mechanical loading imposed on the right ventricle (RV) that results in progressive changes to its mechanics and function. Here, we quantify the mechanical changes associated with PAH by assimilating clinical data consisting of reconstructed three-dimensional geometry, pressure, and volume waveforms, as well as regional strains measured in patients with PAH (n = 12) and controls (n = 6) within a computational modeling framework of the ventricles. Modeling parameters reflecting regional passive stiffness and load-independent contractility as indexed by the tissue active tension were optimized so that simulation results matched the measurements. The optimized parameters were compared with clinical metrics to find usable indicators associated with the underlying mechanical changes. Peak contractility of the RV free wall (RVFW) γRVFW,max was found to be strongly correlated and had an inverse relationship with the RV and left ventricle (LV) end-diastolic volume ratio (i.e., RVEDV/LVEDV) (RVEDV/LVEDV)+ 0.44, R2 = 0.77). Correlation with RV ejection fraction (R2 = 0.50) and end-diastolic volume index (R2 = 0.40) were comparatively weaker. Patients with with RVEDV/LVEDV > 1.5 had 25% lower γRVFW,max (P < 0.05) than that of the control. On average, RVFW passive stiffness progressively increased with the degree of remodeling as indexed by RVEDV/LVEDV. These results suggest a mechanical basis of using RVEDV/LVEDV as a clinical index for delineating disease severity and estimating RVFW contractility in patients with PAH.NEW & NOTEWORTHY This article presents patient-specific data assimilation of a patient cohort and physical description of clinical observations.

Aortic Valve Ejection Fraction for Monitoring Heart Contractility in Patients Supported with a Continuous Flow Left Ventricular Assist Device

Aortic Valve Ejection Fraction for Monitoring Heart Contractility in Patients Supported with a Continuous Flow Left Ventricular Assist Device

A183 Improvement of Left Ventricular Mass Index and Ventricular Contractility in patients with obesity following rapid weight loss after Bariatric Surgery

A183 Improvement of Left Ventricular Mass Index and Ventricular Contractility in patients with obesity following rapid weight loss after Bariatric Surgery

Long-term performance of an atrial lead capable of accelerometer based detection of cardiac contractility in patients receiving cardiac resynchronisation therapy.

ObjectivesTo evaluate the long-term performance of the SonRtip atrial lead.BackgroundTo optimize atrioventricular and interventricular timing and thereby potentially improving cardiac resynchronization therapy (CRT) responder rates, a lead integrated technology and a cardioverter/defibrillator-based algorithm measuring peak endocardial acceleration have been introduced. Long-term performance of the atrial lead (SonRtip PS55D, Sorin/MicroPort CRM, Italy) embedded with such a sensor has not been reported so far.MethodsBetween 2012 and 2018, 143 patients underwent implantation of the SonRtip atrial lead in four Austrian medical centers. Conventional bipolar atrial leads implanted during the same period in 526 patients receiving CRT were used as control cohort.ResultsAmong 669 patients included in the study, 10 (1.5%) showed increased atrial pacing thresholds and/or decreased atrial sensing amplitudes and/or sudden increase in atrial lead impedance (above 3000 Ω) after an uneventful early postoperative period. Seven (70%) of the malfunctioning leads were SonRtip leads (p <0.001). Lead replacement was needed in 4.2% of SonRtip leads (six out of 143) and in 0.38% of all other conventional atrial leads (two out of 526) (p <0.001). Because of unaltered atrial sensing properties, a wait and see strategy was chosen in two patients–one of them with a SonRtip lead. The implanted atrial lead in the latter person experienced a sudden increase in pacing threshold (4V/0.35ms).ConclusionsWhile short-term safety and stable technical performance of the SonRtip atrial lead could be confirmed, our study found an unexpectedly high malfunction rate over a longer follow-up period.

Gallbladder interstitial Cajal-like cells and gallbladder contractility in patients with cholelithiasis: a prospective study.

A reduced number of interstitial Cajal-like cells (ICLCs) in the gallbladder have been proposed to play a role in the pathogenesis of cholelithiasis. Therefore, this prospective study was conducted to investigate the relationship between gallbladder contractility and the number of gallbladder ICLCs in patients with cholelithiasis. Patients admitted to the Department of Hepatobiliary Surgery for cholecystectomy were divided into the cholelithiasis (n = 18) and non-cholelithiasis (n = 8) groups based on their clinical data. Patients' clinical data were collected on admission, and B-mode ultrasonography was performed to assess their gallbladder contractility. The resected gallbladder specimens were fixed, paraffin sections mounted on slides, and the immunofluorescence staining with the anti-human CD-117 and anti-human tryptase antibodies was performed to identify ICLSs and mast cells, respectively. The number of ICLCs was counted in 10 high-power fields (HPFs) randomly. Independent sample t-tests revealed differences between the cholelithiasis and non-cholelithiasis groups in the number of ICLCs (mean ± standard deviation: 88.61 ± 28.22 vs. 115.89 ± 27.87 per HPFs, P = 0.032) and gallbladder contractility (43.94% ± 18.50% vs. 61.00% ± 20.50%, P = 0.046). Pearson and Spearman cor-relation analyses revealed no significant correlation between the number of ICLCs and gallbladder contractility. The results suggest that the number of gallbladder ICLCs in the wall of the gallbladder of patients with or without cholelithiasis is not a decisive factor affecting gallbladder contractility.

Predictors of unfavorable course of acute myocarditis with reduced left ventricular ejection fraction

Early prediction of myocarditis clinical course still remains one of the actual tasks of cardiological science, which has a significant practical value. The purpose of the study was to determine the predictors of unfavorable course of myocarditis with reduced ejection fraction (EF) of the left ventricle (LV) on the basis of follow-up during 24 months. The study included 90 patients with acute myocarditis and reduced LV EF, who were examined in the first month after the disease onset, after 6, 12 and 24 months of follow-up. All patients underwent for echocardiography, Holter monitoring of the electrocardiogram and cardiac magnetic resonance imaging. Statistical processing of the results was performed using the Excel XP software (Місrosoft Office, USA) and Statistica for Windows v. 6.0 (Statsoft, USA). It was found that restoration of cardiac contractility in patients with myocarditis and reduced LV EF began with an increase in the index of LV longitudinal global systolic strain, which occurred 6 months after the debut of the disease and was associated with a decrease in the number of LV segments affected by the inflammatory process, and a significant increase of LV EF and a decrease of LV end-diastolic volume were observed only 1 year after the disease onset. The predictors of cardiovascular events in patients with acute myocarditis during the next 24 months from the onset of the disease, were detected in the 1st month from the debut of the disease and included following pathological changes: value of the LV EF ≤ 30%; reduction of LV longitudinal global systolic strain ≤ 7.0%; evidence of non-sustained ventricular tachycardia, presence of inflammatory changes in ≥6 LV segments, presence of delayed enhancement in ≥ 5 LV segments. Prospects for further research are the creation of registries of patients with myocarditis on the basis of multicenter clinical trial results on a large number of patients surveyed in order to improve diagnosis, prediction of clinical course and identification of early diagnostic markers of cardiovascular events and quantitative risk assessment of their development.

The Inorganic NItrate For eXercise In Heart Failure (INIX-HF) Trial: Rationale, Design, And Preliminary Data

Peak oxygen uptake (VO2peak) and muscle contractile function are both impaired in patients with heart failure with reduced ejection fraction (HFrEF), with these deficits significantly contributing to the diminished quality of life and possibly even early mortality of such individuals. In previous pilot studies, however, we have reported that these deleterious changes can be ameliorated by acute ingestion of nitrate (NO3-), which in vivo can be converted to nitric oxide (NO) via the enterosalivary NO3- → nitrite (NO2-) → NO pathway. PURPOSE Based on these studies, the INIX-HF trial is a proposed multi-center (i.e., 8 site), randomized control trial of the effects of acute (i.e., single dose) and chronic (i.e., 2 wk) dietary NO3- supplementation (in the form of KNO3) on VO2peak and muscle contractility in patients with HFrEF. We are presently performing the work that is necessary and sufficient to set up this trial, including determining the optimal dose of KNO3 to utilize. METHODS Using a double-blind, crossover design, six patients with HFrEF (5 men, 1 woman; age = 49±4 y; EF = 32±3%) were studied 2-3 h after acute ingestion of either 10 or 20 mmol KNO3. On each occasion, VO2peak was measured during an incremental treadmill exercise test (modified Naughton protocol) and muscle function was determined using isokinetic dynamometry. RESULTS The increase in plasma NO3- was greater following ingestion of 20 vs. 10 mmol KNO3 (Δ = 430±51 vs. 218±19 μmol/L; P=0.002). However, plasma NO2- increased to a similar degree in both trials (Δ = 0.219±0.078 vs. 0.169±0.044 μmol/L; P=0.67). Presumably as a result, VO2peak did not differ between treatments (i.e., 18.0±1.5 vs. 17.7±1.3 mL.min-1.kg-1; P=0.74). There was also no difference in maximal knee extensor power (4.52±0.56 vs. 4.25±0.59 W/kg; P=0.69) across trials. 27% of subjects experienced moderate-to-severe nausea and/or vomited after ingesting the higher dose KNO3, vs. only 9% after the lower dose. CONCLUSION There was no difference in the efficacy of 10 vs. 20 mmol KNO3 in influencing VO2peak or muscle power in patients with HFrEF. The higher dose, however, was associated with a greater frequency of gastrointestinal distress. Based on these preliminary data, it appears that 10 mmol KNO3 is the preferred dose for a larger, multicenter trial. Supported by award R34HL138253 from the NHLBI

Tu1285 – Manometric Characteristics of Upper Esophageal Sphincter and Striated Esophageal Contractility in Patients with Ineffective Esophageal Motility

Tu1285 – Manometric Characteristics of Upper Esophageal Sphincter and Striated Esophageal Contractility in Patients with Ineffective Esophageal Motility