OBJECTIVETo assess the accuracy of cardiac output (CO) measured by transpulmonary thermodilution technique (TPTD)and explore the validity of intrathoracic blood volume index (ITBVI) for assessment of circulatory volume status.

METHODSTen immature pigs with a mean weight of (20.6±1.9)kg were studied during the conditions including normovolemia, hypervolemia, and hypovolemia. Simultaneous CO was measured in each condition using pulmonary artery thermodilution (PATD) method and TPTD. More specifically, CO (COPA) was determined with PATD, while CO (COTP) and ITBVI were determined with TPTD. All measurements were repeated 3 times. Central venous pressure (CVP) and heart rate were measured at the same time. The potential correlations of CVP and ITBVI with cardiac index (CI) and stroke volume index (SVI) in each blood volume status were analyzed.

RESULTSA total of 90 simultaneous measurements of COPA and COTP in 3 different blood volume conditions were made. The correlation coefficient between the two measurements was 0.977 (P<0.001) and the mean difference was (0.25±0.26)L/min (95%CI:0.20-0.30 L/min, P<0.001). The coefficient of variation of COTP was 3.7%, while COPA was 5.4%. Compared with those in normovolemia, CVP and ITBVI in hypervolemia significantly increased (P=0.002, 0.019), ITBVI in hypovolemia decreased significantly (P<0.001), and CVP in hypovolemia decreased insignificantly (P=0.05). Correlation analysis revealed a significant correlation between ITBVI with CI and SVI in normovolemia (r=0.741, P=0.014; r=0.885, P=0.001). In contrast, correlations between CVP with CI and SVI were poor.

CONCLUSIONSTPTD can accurately and precisely measure CO in different blood volume conditions. ITBVI measured by TPTD has better validity for the assessment of circulatory volume status than CVP.

Animals ; Blood Volume ; Cardiac Output ; Swine ; Thermodilution

OBJECTIVETo observe the hemodynamic changes in patients undergoing pericardiectomy at different operational stages.

METHODSTotally 16 consecutive patients receiving radical pericardiectomy were enrolled in this observational study. Hemodynamic variables were monitored continuously by pulse-indicated continuous cardiac output(PiCCO)system. Totally,three sets of intraoperative hemodynamic parameters were obtained at three different stages of pericardiectomy.

RESULTSDuring the pericardiectomy,the cardiac index[CI,(1.9±0.6),(2.7±0.6),(3.0±0.5)L·min(-1)·m(-2);P<0.05]and stroke volume index[SI,(22.5±8.7),(29.9±8.5),(30.1±8.5)dyn·s·cm(-5)·m(2);P<0.05]showed significant improvement,whereas central venous pressure[CVP,(17.1±5.0),(13.3±3.9),(12.3±3.0)mmHg;P<0.05]decreased significantly. Global end-diastolic volume index[GEDVi,(533±156),(580±153),(559±144)ml·m(-2);P<0.05]increased and stroke volume variation[SVV,(15.6±6.1)%,(10.8±4.2)%,(9.4±5.4)%;P<0.05]decreased intra-operatively. The majority of the above-mentioned hemodynamic improvements occurred after the resection of pericardium over the left ventricular outflow tract(LVOT).

CONCLUSIONSPiCCO system can serve as a reliable,less invasive hemodynamic monitoring method during pericardiectomy. Resection of the pericardium over the LVOT is the most important step of the pericardiectomy.

Cardiac Output ; Heart ; Heart Rate ; Hemodynamics ; Humans ; Pericardiectomy ; Stroke Volume

PURPOSE: To evaluate quantification results of single breath-hold (SBH) magnetic resonance (MR) cine imaging compared to results of conventional multiple breath-hold (MBH) technique for left ventricular (LV) function in patients with cardiac arrhythmia. MATERIALS AND METHODS: MR images of patients with arrhythmia who underwent MBH and SBH cine imaging at the same time on a 1.5T MR scanner were retrospectively reviewed. Both SBH and MBH cine imaging were performed with balanced steady state free precession. SBH scans were acquired using temporal parallel acquisition technique (TPAT). Fifty patients (65.4 ± 12.3 years, 72% men) were included. End-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), ejection fraction (EF), myocardial mass, and LV regional wall motion were evaluated. RESULTS: EF, myocardial mass, and regional wall motion were not significantly different between SBH and MBH acquisition techniques (all P-values > 0.05). EDV, ESV, and SV were significant difference between the two techniques. These parameters for SBH cine imaging with TPAT tended to lower than those in MBH. EF and myocardial mass of SBH cine imaging with TPAT showed good correlation with values of MBH cine imaging in Passing-Bablok regression charts and Bland-Altman plots. However, SBH imaging required significantly shorter acquisition time than MBH cine imaging (15 ± 7 sec vs. 293 ± 104 sec, P < 0.001). CONCLUSION: SBH cine imaging with TPAT permits shorter acquisition time with assessment results of global and regional LV function comparable to those with MBH cine imaging in patients with arrhythmia.
Arrhythmias, Cardiac* ; Humans ; Retrospective Studies ; Stroke Volume ; Ventricular Function, Left*

Cardiac magnetic resonance (CMR) imaging provides accurate anatomic information and advanced soft contrast, making it the reference standard for assessing cardiac volumes and systolic function. In this review, we summarize the recent advances in CMR sequences. New technical development has widened the use of CMR imaging beyond the simple characterization of myocardial scars and assessment of contractility. These novel CMR sequences offer comprehensive assessments of coronary plaque characterization, myocardial fiber orientation, and even metabolic activity, and they can be readily applied in clinical settings. CMR imaging is able to provide new insights into understanding the pathophysiologic process of underlying cardiac disease, and it can help physicians choose the best treatment strategies. Although several limitations, including the high cost and time-consuming process, have limited the widespread clinical use of CMR imaging so far, recent advances in software and hardware technologies have made the future more promising.
Cardiac Volume ; Cardiology ; Cicatrix ; Heart Diseases ; Magnetic Resonance Imaging

BACKGROUND: The required dose of anesthetics is generally smaller in patients with low cardiac output (CO). A high CO decreases the blood concentration of anesthetics during induction and maintenance of anesthesia. However, a high CO may also shorten the delivery time of anesthetics to the effect site, e.g. the brain. We assessed the time required for induction of anesthesia with propofol administered by target-controlled infusion (TCI), and investigated factors that modify the pharmacodynamics of propofol. METHODS: After measuring CO and blood volume (BV) by dye densitometry, propofol was infused using TCI to simulate a plasma concentration of 3 microg/ml. After infusion, the time taken to achieve bispectral index (BIS) values of 80 and 60 was determined. Age, sex, lean body mass (LBM), and cardiovascular parameters were analyzed as independent variables. The dependent variables were the time taken to achieve each BIS value and the plasma concentration of propofol (Cp) 10 min after the commencement of infusion. RESULTS: Multiple regression analysis revealed that a high CO significantly reduced the time taken to reach the first end point (P = 0.020, R2 = 0.076). Age and LBM significantly prolonged the time taken to reach the second end point (P = 0.001). Cp was negatively correlated with BV (P = 0.020, R2 = 0.073). CONCLUSIONS: Cardiac output was a statistically significant factor for predicting the time required for induction of anesthesia in the initial phase, whereas, age and LBM were significant variables in the late phase. The pharmacodynamics of propofol was intricately altered by CO, age, and LBM.
Anesthesia ; Anesthetics ; Blood Volume ; Brain ; Cardiac Output ; Cardiac Output, Low ; Consciousness Monitors ; Densitometry ; Humans ; Plasma ; Propofol

The addition of femoral-femoral cardiopulmonary bypass in the cardiac catheterization laboratory to support the high risk patient is a challenging new frontier for percutaneous transluminal coronary angioplasty. We report our first experience of successful supported angioplasty in patient presented with exertional angina and orthopnea who had multi-vessel coronary artery disease with depressed left ventricular ejection fraction. Although cardiopulmonary support provides excellent support for high-risk patient, CPS is a technically challenging and expensive procedure associated with significant patient morbidity or complication. Despite its drawbacks, CPS has been shown to help save the lives of selected patients undergoing high-risk procedures.
Angioplasty ; Angioplasty, Balloon, Coronary* ; Cardiac Catheterization ; Cardiac Catheters ; Cardiopulmonary Bypass ; Coronary Artery Disease ; Humans ; Stroke Volume

OBJECTIVETo observe the sensitivity of stroke volume variation (SVV) for assessing volume change during induction period of general anesthesia.

METHODSPatients who underwent orthopaedic surgery under general anesthesia and mechanical ventilation were divided into two groups randomly. Patients in the group Ⅰwere subjected to progressive central hypovolemia and correction of hypovolemia sequentially; patients in the Group Ⅱ were exposed to hypervolemia alone. Each step was implemented after 5 minutes when the hemodynamics was stable. SVV and cardiac index (CI) were recorded, and Pearson's product-moment correlation was used to analyze correlation between SVV and CI.

RESULTSForty patients were included in this study, 20 cases in each group. For group Ⅰ patients, SVV was increased significantly along with blood volume reduction, and changes in CI were negatively correlated with changes in SVV (r=-0.605, P<0.01); SVV decreased significantly along with correction of blood volume; changes in CI were negatively correlated with changes in SVV (r=-0.651, P<0.01). For group Ⅱ patients, along with blood volume increase, SVV did not change significantly; changes in CI revealed no significant correlation with changes in SVV (r=0.067, P>0.05).

CONCLUSIONSVV is a useful indicator for hypovolemia, but not for hypervolemia.

Adult ; Aged ; Arterial Pressure ; Blood Volume ; Cardiac Output ; Central Venous Pressure ; Female ; Humans ; Male ; Middle Aged ; Perioperative Period ; Stroke Volume

BACKGROUND: Long-term survival after surgical correction of mitral regurgitation is associated with preservation of left ventricular systolic function after operation. And mitral valve repair has been suggested to provide a better postoperative left ventricular systolic function. Accordingly, we intended to compare the operative results of mitral valve repair with those of mitral valve replacement and search for preoperative predictors of postoperative left ventricular systolic function. METHOD: The clinical features, echocardiographic measurements, and cardiac catheterization results of 75 patients operated between January 1984 and December 1994 for acquired pure mitral regurgitation were analyzed. RESULTS: Of the 75 patients, 39 patients had mitral valve repair, and 36 patients had mitral valve replacement. When the outcomes of mitral valve repair and mitral valve replacement were compared, left ventricular ejection fraction decreased significantly after surgery inboth groups but postoperative left ventricular ejection fraction was greater in valve repair group than in valve replacement group. Data analysis of preoperative variables showed that echocardiographic left ventricular end-diastolic diameter(p<.05), but not other clinical and echocardiographic variables, were predictors of postoperative left ventricular systolic function. CONCLUSION: After surgical correction of chronic organic mitral regurgitation, left ventricular dysfunction is frequent and valve repair decreases the severity of left ventricular dysfunction. And the most powerful predictor of postoperative left ventricular systolic function is preoperative left ventricular end-diastolic diameter measured by echocardiography.
Cardiac Catheterization ; Cardiac Catheters ; Echocardiography ; Humans ; Mitral Valve Insufficiency* ; Mitral Valve* ; Statistics as Topic ; Stroke Volume ; Ventricular Dysfunction, Left

BACKGROUND AND OBJECTIVES: The reliability and usefulness of the right ventricular (RV) Tei index (RTX) remains controversial because it has not been possible to simultaneously measure RV inflow and outflow. However, dual pulsed-wave Doppler (DPD) enables flow velocities to be obtained at different sampling sites simultaneously. In this study we evaluated the feasibility and reliability of RTX values obtained by DPD (RTX(DPD)). SUBJECTS AND METHODS: Forty-one patients who underwent cardiac catheterization and echocardiography for RV volume or pressure overloading conditions were evaluated. Symptom-limited exercise treadmill testing with expired gas analysis was performed and maximal exercise capacity was measured. RESULTS: RTX by conventional flow Doppler (RTX(CFD), 0.262+/-0.164) was similar to RTX(DPD) (0.253+/-0.117, p=NS), whereas RTX by tissue Doppler echocardiography (RTX(TDE), 0.447+/-0.125) was significantly larger than RTX(DPD) (p<0.001). Based on multiple regression analysis, maximal exercise capacity was independently related to RTX(DPD) (beta=-0.60, p<0.001), mid-RV dimension (beta=-0.26, p=0.012), left ventricular ejection fraction (beta=0.22, p=0.023), and early diastolic tricuspid annular velocity (beta=0.21, p=0.048). CONCLUSION: It is feasible and reliable to evaluate RV function using RTX(DPD) values. However, to evaluate the clinical usefulness of RTX(DPD), additional studies are required with a large number of patients and long-term follow-up.
Cardiac Catheterization ; Cardiac Catheters ; Echocardiography ; Echocardiography, Doppler ; Echocardiography, Doppler, Pulsed ; Exercise Test ; Heart Ventricles ; Humans ; Stroke Volume ; Ventricular Function, Right

OBJECTIVETo assess the influence of mimic cardiac rate on hydrodynamics of different mechanical prosthetic cardiac valves.

METHODSUS-made CarboMedics bileaflet valve, China-made Jiuling bileaflet valve and C-L tilting disc valve were tested via a pulsatile flow simulator in the aortic position. Testing conditions were set at mimic cardiac rates of 55 bpm, 75 bpm, 100 bpm with a constant mimic cardiac output of 4 L/min. The mean pressure differences (deltaP), leakage volumes (L(E)V) and closing volumes (C(L)V) across each valve, and effective orifice areas (EOA) were analyzed.

RESULTSWithin physiological range, deltaP, L(E)V, and C(L)V decreased as mimic cardiac rate increased, with a large extent of variance. EOA increased along with an increase in mimic cardiac rate. It was a different response in terms of cardiac rate alteration for different types of mechanical prosthetic cardiac valves.

CONCLUSIONMimic cardiac rate change affects hydrodynamics of mechanical prosthetic cardiac valves. Within physiological range, the hydrodynamic of prosthetic bileaflet valve is better than that of tilting disc valve.

Biomechanical Phenomena ; Cardiac Output ; Cardiac Volume ; Heart Rate ; Heart Valve Prosthesis ; Hemodynamics ; In Vitro Techniques ; Prosthesis Design ; Pulsatile Flow