Inferring high-resolution human mixing patterns for disease modeling

Mathematical and computational modeling approaches are increasingly used as quantitative tools in the analysis and forecasting of infectious disease epidemics. The growing need for realism in addressing complex public health questions is, however, calling for accurate models of the human contact patterns that govern the disease transmission processes. Here we present a data-driven approach to generate effective population-level contact matrices by using highly detailed macro (census) and micro (survey) data on key socio-demographic features. We produce age-stratified contact matrices for 35 countries, including 277 sub-national administratvie regions of 8 of those countries, covering approximately 3.5 billion people and reflecting the high degree of cultural and societal diversity of the focus countries. We use the derived contact matrices to model the spread of airborne infectious diseases and show that sub-national heterogeneities in human mixing patterns have a marked impact on epidemic indicators such as the reproduction number and overall attack rate of epidemics of the same etiology. The contact patterns derived here are made publicly available as a modeling tool to study the impact of socio-economic differences and demographic heterogeneities across populations on the epidemiology of infectious diseases.

Comparison of Serum Electrolytes Abnormality and Renal Function Status in Asphyxiated and Normal Baby in a Tertiary Level Hospital

Complication of perinatal asphyxia is a major cause of neonatal mortality & morbidity in developing countries. This comparative cross sectional study was conducted in Mymensingh Medical College Hospital, Mymensingh, Bangladesh from May 2012 to September 2012 to determine electrolytes & renal function status in perinatal asphyxia & their impact on outcome. Thirty term normal birth weight babies with perinatal asphyxia in neonatal ward were included as a case group and thirty term normal birth weight neonates of same gestational age, without perinatal asphyxia in the department of Gynae & Obs were enrolled as a control group. Necessary information was collected by clinical examination; investigation and close follow up according to predetermined plan. There was no significant different in sex distribution, number of Antenatal care (ANC), number of gravidum of mother and mode of delivery between two groups. Among perinatal Asphyxia group most common risk factor was prolonged labor. Electrolyte abnormalities were documented (16) 53.3% cases. Among 16 electrolyte abnormalities isolated hyponatremia was found in 6(37.5%) cases, hyponatremia with hyperkalaemia 1(6.25%) case, hyponatremia with hypokalaemia in 1(6.25%) case, isolated hypokalaemia in 3(18.75%) cases and isolated hyperkalaemia in 5(31.25%) cases. None case had hypernatremia. On the other hand in control group Hypokalaemia was 3(10%) cases Hyperkalaemia 1(33.33%) case and none had Hyponatraemia. Among total cases 6 (20%) had renal impairment. Serum creatinine level was higher in case group. Twenty percent (20%) case initial value >1.5mg/dl, 20% 1.2-1.5mg/dl and17% had 0.3-0.8mg/dl. On the other hand in control group 83 % had 0.3-0.8 mg/dl & none hade above 1.1 mg/dl. Among case group 8 were died (27%). There was no death in control group. Among 8 neonatal death cases 3(37.5%) had normal electrolytes, isolated hyponatraemia were in 2(25%) cases, hyponatraemia with Hyperkalaemia in 1(6.25%) case and Isolated Hyperkalaemia in 2(25%) cases. Among those death 3(37.5%) had renal impairment. Case fatality was significantly associated with renal failure 50%, isolated Hyponatraemia 33.33%, Isolated hyperkalaemia 40%, Hyperkalaemia with Hyponatremia 100%. Hospital stay was also prolonged among alive case with abnormal electrolytes. So, we can conclude that electrolyte & renal impairments are significantly associated with morbidity & mortality of perinatal Asphyxia.

HPLC-CUPRAC post-column derivatization method for the determination of antioxidants: a performance comparison between porous silica and core-shell column packing

BACKGROUND

An HPLC method employing a post-column derivatization strategy using the cupric reducing antioxidant capacity reagent (CUPRAC reagent) for the determining antioxidants in plant-based materials leverages the separation capability of regular HPLC approaches while allowing for detection specificity for antioxidants.

METHODS

Three different column types, namely core-shell and porous silica including two chemically different core-shell materials (namely phenyl-hexyl and C18), were evaluated to assess potential improvements that could be attained by changing from a porous silica matrix to a core-shell matrix. Tea extracts were used as sample matrices for the evaluation specifically looking at catechin and epigallocatechin gallate (EGCG).

RESULTS

Both the C18 and phenyl-hexyl core-shell columns showed better performance compared to the C18 porous silica one in terms of separation, peak shape, and retention time. Among the two core-shell materials, the phenyl-hexyl column showed better resolving power compared to the C18 column.

CONCLUSIONS

The CUPRAC post-column derivatization method can be improved using core-shell columns and suitable for quantifying antioxidants, exemplified by catechin and EGCG, in tea samples.

Klippel Trenaunay Syndrome: A Case Report

Klippel Trenaunay syndrome refers to a rare congenital anomaly which is characterized by capillary malformation, venous malformation and sometimes lymphatic malformation associated with overgrowth of a limb, with soft tissue hypertrophy and/or bony hypertrophy. The anomaly, if present, is present at birth and usually involves the lower limbs as well as portion of trunk, face, uppper limb or head. Our reporting case is a preterm male neonate having port wine stain, varicose veins and excessive growth of soft tissue of left lower limb clinically consistent with Klippel Trenaunay Syndrome.

Status of Low Birth Weight Babies in Mymensingh Medical College Hospital

Low birth weight (LBW) is the major neonatal health problem in Bangladesh like other developing countries with limited resource. But only a few studies had done about status of LBW at hospital setting in this country. The objective of the study that to evaluate the status and immediate outcome of the LBW This cross sectional retrospective study was done in neonatal ward of Mymensingh medical college hospital. In this 1000 bedded tertiary care level teaching hospital only 40 cots and 10 open incubators are sanctioned but daily average admission in neonatal ward more than 30. On an average about 100 patients are remaining in the ward. Three or four patients are nursed in each cot. It covers the vast catchment's area of Bangladesh having more than two cores of population. With limited resources and manpower, this neonatal ward has to bear the burden of 100 neonates and daily admission of 30 neonates. Study period was one year (October 2013 to September 2014). Total admitted neonates were 8359. All admitted neonates were considered as study population and all LBW babies were considered as sample. Among total population 41% (3423) were LBW. Among total LBW babies maximum (80.7%) had birth weight 1500-2499gm followed by Very Low birth weight (VLBW) 1000 - 1499gm 14.7%, Extreme Low birth weight (ELBW) 1000-750gm 1.6% and Incredible low birth weight <750gm 1.7%. Term LBW (IUGR) babies were 52% and preterm LBW were 48%. Death rate among LBW babies group were higher (18.5%) than death rate (15.8%) among all admitted neonate. By comparison of mortality rate among different subgroup of LBW shows highest mortality (65.5%) was in incredible low birth weight babies group followed by ELBW group (58.8%) and among VLBW group 26.4% and lowest mortality (15.3%) was among birth weight 1500-2499gm group babies. Death rate was inversely related to birth weight. Death rate among preterm LBW babies (21.5%) was higher than Term LBW (IUGR) babies (15.7%). So, death rate was also inversely related to the maturity. Death rate among LBW babies is still higher in our institute than other developed institute of home and abroad. Death rate specially higher among incredible birth weight group and ELBW group in our institute. Further improvement in neonatal care is needed to decrease the mortality among LBW babies.

Solution and structural binding studies of phosphate with thiophene-based azamacrocycles

Two thiophene-based monocyclic receptors L1 and L2 have been studied for phosphate binding in solutions (D2O and DMSO-d6 ) by 1H NMR and 31P NMR titrations, and in the solid state by single crystal X-ray analysis. Results from 1H NMR titrations suggest that the ligands bind phosphate anions in a 1:2 binding mode in DMSO-d6 , with the binding constants of 5.25 and 4.20 (in log K), respectively. The binding of phosphate to L1 and L2 was further supported by 31P NMR in D2O at pH = 5.2. The crystal structure of the phosphate complex of L1 reveals unambiguous proof for the formation of a ditopic complex via multiple hydrogen bonds from NH···O and CH···O interactions.

Experimental and Theoretical Aspects of Anion Complexes with a Thiophene-Based Cryptand

Selective recognition of anions has received a tremendous attention in recent years because of their significant importance in biology and environment. This article highlights our recent research on a thiophene-based azacryptand that has been shown to effectively bind anions including iodide, bromide, chloride, nitrate and sulfate. Structural studies indicate that the ligand forms inclusion complexes with chloride and iodide. On the other hand, it forms cleft-like complexes with nitrate and sulfate, where three anions are bound between the cyclic arms. The ligand binds each anion with a 1:1 binding mode in water, exhibiting strong selectivity for sulfate; which is further supported by ESI-MS and DFT calculations.

Incomplete Pentalogy of Cantrell--A Case Report

Cantrell's Pentalogy is a rare congenital malformation consists of supraumbilical abdominal wall defect, defect in the lower part of sternum, agenesis of anterior portion of diaphragm, an absence of the diaphragmatic part of the pericardium and intracardiac malformation. This case report presents a female neonate, who was born at 40 weeks of gestation weighing 2400 gm and was admitted 4 hours after delivery with the complaints of something coming out from chest. On physical examination her vital signs were within normal limit, she had a systolic murmur on heart at lower left sternal area and there was a vascular structure present on the upper part of abdomen which was pulsatile and pulsation was synchronized with cardiac pulsation. On investigation chest X-ray lateral view showed absence of lower part of sternum, echocardiography findings were different in different institutes. Echocardiography findings at Mymensingh medical college hospital (MMCH) were large VSD (Ventriculo septal defect), ASD (Atrial septal defect) and rotated heart. On colour Doppler ultrasonogram at MMCH showed there were VSD, ASD, and a small epigastric swelling which was vascular and appears to be attached to the apex of the heart. On the other hand echocardiography findings of LAB AID hospital in Dhaka were Dextrocardia, complete AV (atrio ventricular) canal defect, almost common atrium, almost single ventricle, common AV valve, double outlet right ventricle (DORV), Cortriatriatum, mild A-V valve regurgitation and severe pulmonary hypertension (PAH). Echocardiography was also done at national heart foundation hospital in Dhaka. Findings were situs solitus, mesocardia to dextrocardia, DORV, large VSD, mild mitral inflow, mild TR (triuspid regurgitation), good LV (left ventricle) and RV (right ventricle) systolic function. Cardiologists at Dhaka in Bangladesh were suggested for surgery. Then the patient was consulted at Naryan Institute of Cardiac Science, Chennai in India. Here echocardiography findings were dextroversion/dextrocardia, DILV (Double inlet left ventricle), large inlet VSD with bidirectional shunt, mild TR, severe PAH with good ventricular function. Cardiologists in India were given comment about this patient. This patient was highly risky for surgery. They advised medical treatment and requested to review after one year. By taking medical treatment patient condition is well except failure to thrive and cyanosis develops during feeding and crying according to the statement of guardian of the patient. This case has 3 criterias among the five criteria of Cantrell's Pentalogy. So, it is incomplete Pentalogy of Cantrell.

Crystal structure of 5,5'-bis-(di-methyl-amino)-N,N'-(3-methyl-3-aza-pentane-1,5-di-yl)di(naphthalene-1-sulfonamide)

In the title compound, C29H37N5O4S2, two arms substituted with dansyl derivatives are connected to a central tertiary amine, where the dihedral angle between the planes of two dansyl units is 56.39 (4)°. Each arm contains a sulfonamide functional group and both N-H groups in the compound are pointed to the same side. The central part of the mol-ecule is disordered over three sets of sites with a refined occupancy ratio of 0.547 (4):0.328 (4):0.125 (3). No intra-molecular π-π or hydrogen-bonding inter-actions are observed. In the crystal, mol-ecules are linked via pairs of N-H⋯O inter-actions involving the same acceptor atom, forming inversion dimers. In addition, C-H⋯O inter-actions exist between molecules, providing further stabilization of dimers.

Immediate Clinical and Echocardiographic Outcome of Percutaneous Transvenous Mitral Commissurotomy for Patients of Mitral Stenosis with Atrial Fibrillation

Rheumatic fever and rheumatic heart disease continue to be the major health problem in all developing countries including Bangladesh. Rheumatic mitral stenosis is a very common problem in our population having an incidence of 54 percent among rheumatic heart disease with a female preponderance of 2:1. Percutaneous balloon mitral commissurotomy is appealing because the mechanism of valve dilation closely parallels the mechanism of surgical mitral commissurotomy. The technique of balloon mitral commissurotomy has evolved rapidly, with improvements in balloons, guide wires, and the application of double-balloon techniques. There is controversy that whether the presence of AF has a direct negative effect on the immediate or long-term outcome after PTMC in mitral stenosis patients. The purpose of this study was to see the effect of atrial fibrillation (AF) on the immediate clinical and echocardiographic outcome of patients undergoing Percutaneous Transvenous Mitral Commissurotomy (PTMC). The immediate procedural and in-hospital clinical outcome after PTMC of 264 patients with AF were prospectively collected and compared with those of 288 patients in normal sinus rhythm (NSR) with mitral stenosis admitted in National Institute of Cardiovascular Diseases, Dhaka and Al-Helal Heart Institute, Mirpur, Dhaka, Bangladesh. Patients with AF were older than patients with normal sinus rhythm (53 ± 11 vs. 33 ± 12 years; p<0.0001) and presented more frequently with New York Heart Association (NYHA) class III-IV (78.3% vs. 58.5%; p<0.0001), echocardiographic score >8 (38.9% vs. 22.7%; p<0.0001), calcified valves under fluoroscopy (22.2% vs.12.4%, p<0.0001) and with history of previous surgical commissurotomy (21.7% vs. 10.5%; p<0.0001). In patients with AF, PTMC resulted in worse outcomes, as reflected in a smaller post-PTMC mitral valve area (1.6±0.4 vs. 2.1 ± 0.8 cm²; p<0.0001). Patients with atrial fibrillation have a worse immediate clinical and echocardiographic outcome after PTMC.

Formation of porous SnS nanoplate networks from solution and their application in hybrid solar cells

Herein, we present a facile solution-based route towards nanostructured, hybrid absorber layers based on tin mono-sulfide (SnS), an emerging, non-toxic absorber material for low-cost and large-scale PV applications. Charge photogeneration properties in the hybrid system are studied using transient absorption spectroscopy and fabricated solar cells show efficient photocurrent generation over a broad spectral range.

Colorimetric and Optical Discrimination of Halides by a Simple Chemosensor

A thiophene-based tripodal copper(II) complex has been synthesized as a new colorimetric and optical chemosensor for naked-eye discrimination of halides in acetonitrile and an acetonitrile-water mixture. The binding interactions of the new receptor with several anions were analyzed by UV-Vis titrations, electrospray ionization mass spectrometric (ESI-MS) experiments and density functional theory (DFT) calculations. The results from UV-Vis titrations indicate that the coordinative unsaturated copper(II) complex strongly binds a halide at its vacant copper(II) centre via a metal-ligand bond forming a 1:1 complex, exhibiting binding affinities in the order of fluoride > chloride > bromide > iodide. The interactions of the receptor with halides were further confirmed by ESI-MS, showing a distinct signal corresponding to a 1:1 complex for each halide, suggesting that the noncovalent interactions also exist in the gas phase. In addition, time-dependent DFT (TD-DFT) calculations were also carried out to understand the excited-state properties of the chemosensor complexes. A detailed analysis of the TD-DFT calculations shows a consistent red-shift in the first optically-allowed transition, consistent with the observed colorimetric experiments.

Improved electronic coupling in hybrid organic-inorganic nanocomposites employing thiol-functionalized P3HT and bismuth sulfide nanocrystals

In this study, we employ a thiol-functionalized polymer (P3HT-SH) as a leverage to tailor the nanomorphology and electronic coupling in polymer-nanocrystal composites for hybrid solar cells. The presence of the thiol functional group allows for a highly crystalline semiconducting polymer film at low thiol content and allows for improved nanomorphologies in hybrid organic-inorganic systems when employing non-toxic bismuth sulfide nanocrystals. The exciton dissociation efficiency and carrier dynamics at this hybrid heterojunction are investigated through photoluminescence quenching and transient absorption spectroscopy measurements, revealing a larger degree of polaron formation when P3HT-SH is employed, suggesting an increased electronic interaction between the metal chalcogenide nanocrystals and the thiol-functionalized P3HT. The fabricated photovoltaic devices show 15% higher power conversion efficiencies as a result of the improved nanomorphology and better charge transfer mechanism together with the higher open circuit voltages arising from the deeper energy levels of P3HT-SH.

Molecular Recognition of Perchlorate Anion With a Cryptand-Based Synthetic Receptor

Perchlorate anion is a highly toxic environmental contaminant, which is implicated in various health related problems. This paper reports a cryptand-based synthetic molecule (L) prepared from the reaction of tris (2-aminoethyl) amine and 2,5-thiophenedicarboxaldehyde under a high dilution condition, providing a well-defined cavity for a guest species. The hexaprotonated receptor [H₆L]⁶⁺ has been obtained from the addition of six equivalents of tosylic acid to L, which has been studied for perchlorate anion by proton NMR studies in water. The results demonstrate that the receptor strongly binds the negatively charged perchlorate via hydrogen bonding and electrostatic interactions in solution forming a supramolecular anion complex. This molecule can be useful for the future application in the environmental remediation of toxic perchlorate anion.

Correlation between grades of intraventricular hemorrhage and severity of hypoxic ischemic encephalopathy in perinatal asphyxia

This study was done to find out the correlation between various grades of Intraventricular Hemorrhage (IVH) and stages of HIE in perinatal asphyxia and to determine the short-term outcome of the affected baby. This observational study was conducted in Neonatal ward of Dhaka Shishu Hospital (DHS) and Dhaka Medical College Hospital for period of 37 months from January 2004 to January 2007. Total 189 perinatally asphyxiated babies were enrolled for HIE staging and cranial Ultrasonogram (USG) to find out grades of IVH. Finally 178 newborns were fulfilling all the necessary criteria for statistical analysis of the collected data on prescribed questionnaire. Among 178 perinatally asphyxiated newborns HIE stages - I, II, III were 50(28%), 10(56%) and 28(16%) respectively. Out of this 178 neonates total 50(28%) developed various grades IVH. Grades of IVH, I, II, III, IV were 15(30%), 18(36%), 10(20%) and 7(14%) respectively. There was significant correlation between the severity of HIE staging and grades of IVH. Short term outcome was poor in HIE-III, IVH grade III and IV. There is a direct relationship between different grades of IVH and stages of HIE. That is more the severe stages of HIE there is more chances to develop severe grades of IVH, Immediate morbidity and mortality is dependent on the grades of IVH and severity of stages of HIE.

N (1)-(Thio-phen-2-ylmeth-yl)-N (3),N (3)-bis-[3-(thio-phen-2-yl-methyl-ammonio)-prop-yl]propane-1,3-di-ammonium hexa-fluorido-silicate methanol tris-olvate

In the title compound, C₂₄H₄₀N₄S₃⁴⁺·2SiF₆²⁻·3CH₃OH, the central tertiary amine function is protonated and is connected to three thio­phen-2-yl­methyl­amino-n-propyl groups, forming the arms of a T-shaped cation that has two pockets. Each arm contains one protonated secondary amine function, and each pocket is occupied by one SiF₆²⁻ anion bonded via two N—H⋯F inter­actions with the protonated amine group on the middle arm, while two methanol solvent mol­ecules are N—H⋯O hydrogen-bonded with the other secondary protonated amine groups on the side arms. Weak O—H⋯O and O—H⋯F hydrogen bonds between the solvent mol­ecules and between the solvent mol­ecules and the anions, respectively, are also observed. All three thio­phene groups in the arms are disordered over two sets of sites, with occupancy ratios of 0.828 (3):0.172 (3), 0.910 (2):0.090 (2) and 0.890 (3):0.110 (3).

Value of red cell distribution width (RDW) and RBC indices in the detection of iron deficiency anemia

Iron deficiency anemia is the common problem during pregnancy. Detection of iron deficiency early during pregnancy can reduce maternal and child mortality and morbidity. Red cell distribution width is a new routine parameter in fully automated hematology analyzer that can give the idea of early iron deficiency before other test. It gives the idea of red cell size variation which is the earliest morphologic changes in iron deficiency anemia. In prelatent and latent stage of iron deficiency MCV are normal. Whereas in latent stage Red Cell Distribution Width (RDW) would be expected to increase because of a microcytic population of cells appears in the blood. This study evaluates the role of red cell distribution width and RBC indices in determining iron deficiency early and provide reliable and useful technique. In this study 190 pregnant women were included. RDW, MCV, MCH, MCHC and iron profile were done. RDW compared with MCV, MCH and MCHC in various stages of iron deficiency. In latent stage of iron deficiency higher RDW was found significant than MCV, MCH, MCHC (p<0.05). In this study RDW had sensitivity 82.3% and specificity 97.4%. Whereas MCV, MCH and MCHC had 29.2%, 68.1% and 15% sensitivity but specificity was 98.7%, 83.1% and 96.1% in the detection of iron deficiency. Iron deficiency anaemia without other complicating disease could be screened out early by increased RDW when RBC indices were normal.

A self-assembled fluoride-water cyclic cluster of [F(H2O)]4(4-) in a molecular box

We present an unprecedented fluoride-water cyclic cluster of [F(H(2)O)](4)(4-) assembled in a cuboid molecular box formed by two large macrocycles. Structural characterization reveals that [F(H(2)O)](4)(4-) is assembled by strong H-bonding interactions [OH···F = 2.684(3)-2.724(3) Å], where a fluoride anion plays the topological role of a water molecule in the classical cyclic water octamer. The interaction of fluoride was further confirmed by (19)F NMR and (1)H NMR spectroscopies, indicating the encapsulation of the anionic species within the cavity in solution. High-level DFT calculations and Bader topological analyses fully support the crystallographic results, demonstrating that the bonding arrangement in the fluoride-water cluster arises from the unique geometry of the host.

Role of red cell distribution width (RDW) in the detection of iron deficiency anaemia in pregnancy within the first 20 weeks of gestation

Iron deficiency anemia is common problem during pregnancy. Red cell size variation (anisocytosis) is the earliest morphologic changes in iron deficiency anemia. Red cell distribution width is a quantitative measure of red cell size variation and it can give the idea of early iron deficiency before other test to become positive. 190 pregnant women were included in this study. Red cell distribution width was compared between iron deficient & non-iron deficient pregnant women. Red cell distribution width also compared with Hb level, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration and peripheral blood film in prelatent iron deficiency, latent iron deficiency, mild and moderate iron deficiency anemia. Red cell distribution width had sensitivity 82.3% and specificity 97.4%. Whereas Hb level, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration and peripheral blood film all had 56.6%, 29.2%, 68.1%, 15% and 38.9% sensitivity but specificity was 90.9%, 98.7%, 83.1%, 96.1% and 98.7% in the detection of iron deficiency. Red cell distribution width appears to be a reliable and useful parameter for detection of iron deficiency during pregnancy.

Long-term results of surgical decompression of thoracic outlet compression syndrome

BACKGROUND

Thoracic outlet compression syndrome is characterised by a variety of symptoms relating to compression of the neurovascular bundle. Though no one test is specific for the syndrome, relief of symptoms may be obtained following surgery in up to 99% of cases.

PATIENTS AND METHODS

The notes of 118 patients operated on in 126 operations by a single surgeon using a supraclavicular approach were reviewed. Symptoms, pre-operative investigations, and complications were all documented. Outcome at 6 weeks, 6, 12 and 24 months follow-up was also recorded. In addition, 61 patients were contacted by telephone, in order to assess current level of symptoms.

RESULTS

Symptoms were predominantly motor, sensory or vasomotor, and were present for a mean of 19.6 months prior to surgery. Complications were rare, but included a pneumothorax requiring a chest drain (n = 1) and infraclavicular anaesthesia (n = 13). The mean duration of hospital stay was 2.1 days. At 6 weeks follow up, 86.5% of patients reported either an improvement, or complete resolution of their symptoms. Sixty-one patients were contactable, a mean of 55 months following decompression. Of these, 44 (72.1%) were either improved or asymptomatic.

CONCLUSION

Decompression for thoracic outlet compression syndrome through a supraclavicular approach encompassing first rib resection leads to good long-term results with few complications.

An enhanced method for measuring cardiac output using Doppler color flow echocardiography

An enhanced method for determining cardiac output using Doppler color flow imaging techniques to measure mitral orifice diameter was developed and validated in an experimental model and in clinical patients. In an in vitro circuit model, color jet width correlated well with actual orifice dimension from 12 to 24 mm (r = 0.99). In the clinical application, mitral valve area was calculated as a X b X pi/4 where a and b represent the width of the color flow stream in the mitral orifice just distal to the annulus in apical long-axis (short-diameter) and 4-chamber (90 degrees rotated, long-diameter) views, respectively. Cardiac output was then computed as the product of mitral valve area and time-velocity integral of transmitral flow from the same site. Cardiac output was also measured by thermodilution and conventional echocardiographic methods using diameters and time-velocity integrals from the left ventricular outflow tract. In 30 patients with nonvalvular heart disease, cardiac output measured by thermodilution ranged from 3.40 to 8.40 L/min. Cardiac output was determined in 28 of 30 patients (93%) by the Doppler color flow imaging technique; it ranged from 3.00 to 8.36 L/min and correlated well with thermodilution: y = 0.90x + 0.63, r = 0.91. Cardiac output was determined in 24 of 30 patients by the conventional left ventricular outflow method (80%). The cardiac output measured by the conventional method correlated less closely with thermodilution (r = 0.84), although there was no statistical difference in correlation coefficiencies between the 2 methods. These results indicate that the Doppler color flow imaging technique can be used to enhance the determination of cardiac output by echocardiography, particularly when the conventional method has resulted in technically inadequate recordings.