Doppler echocardiography for assessment of systemic vascular resistances in cardiogenic shock patients.

OBJECTIVE: Impaired vascular tone plays an important role in cardiogenic shock. Doppler echocardiography provides a non-invasive estimation of systemic vascular resistance. The aim of the present study was to compare Doppler echocardiography with the transpulmonary thermodilution method for the assessment of systemic vascular resistance in patients with cardiogenic shock. METHODS: This prospective monocentric comparison study was conducted in a single cardiology intensive care unit (Hopital Nord, Marseille, France). We assessed the systemic vascular resistance index by both echocardiography and transpulmonary thermodilution in 28 patients admitted for cardiogenic shock, on admission and after the introduction of an inotrope or vasopressor treatment. RESULTS: A total of 35 paired echocardiographic and transpulmonary thermodilution estimations of the systemic vascular resistance index were compared. Echocardiography values ranged from 1309 to 3526 dynes.s.m2/cm5 and transpulmonary thermodilution values ranged from 1320 to 3901 dynes.s.m2/cm5. A statistically significant correlation was found between echocardiography and transpulmonary thermodilution (r=0.86, 95% confidence interval (CI) 0.74, 0.93; P<0.0001). The intraclass correlation coefficient was 0.84 (95% CI 0.72, 0.92). The mean bias was -111.95 dynes.s.m2/cm5 (95% CI -230.06, 6.16). Limits of agreement were -785.86, 561.96. CONCLUSIONS: Doppler echocardiography constitutes an accurate non-invasive alternative to transpulmonary thermodilution to provide an estimation of systemic vascular resistance in patients with cardiogenic shock.

Additional value of lateral tissue Doppler imaging in the assessment of diastolic dysfunction among subjects with pseudonormal pattern of mitral inflow.

BACKGROUND: There has been a lack of research on further stratification of subjects who have pseudonormal pattern of mitral inflow. The study aim was to clarify 2 different groups with different diastolic function grades among these subjects using lateral tissue Doppler imaging (TDI). METHODS: A total of 122 consecutive subjects showing pseudonormal pattern of mitral inflow (E/A ≥ 1 and septal e'/a' < 1) without structural abnormality were prospectively recruited. TDI measurements were performed from both septal and lateral mitral annuli. RESULTS: Study subjects were stratified according to lateral TDI pattern (e'/a' < 1 [n = 50] versus e'/a' ≥ 1 [n = 72]). Subjects with lateral e'/a' < 1 had higher values of left atrial volume index (LAVI) and E/e' compared to those for lateral e'/a' ≥ 1 (p < 0.001 for each). Among subjects with lateral e'/a' ≥ 1, only 9.3% of subjects had grade II diastolic dysfunction, whereas among subjects with lateral e'/a' < 1, majority of subjects (64.1%) had grade II diastolic dysfunction (p < 0.001). Multiple linear regression analysis showed that lateral e'/a' was independently associated with LAVI (ß = -0.484, p < 0.001), even after adjusting for potential confounders including age, sex, body mass index, hypertension and diabetes. CONCLUSIONS: In subjects without structural abnormality showing E/A ≥ 1 and septal e'/a' < 1, lateral TDI measurement is useful in the assessment of diastolic dysfunction. Lateral e'/a' ≥ 1 is a valuable indicator of early diastolic dysfunction but not of advanced diastolic dysfunction in this population.

The diagnostic accuracy of Doppler echocardiography in assessment of pulmonary artery systolic pressure: a meta-analysis.

BACKGROUND: Transthoracic echocardiography is commonly used to estimate pulmonary arterial systolic pressure (PASP) and to diagnose pulmonary hypertension (PH). However, some recent studies have questioned the accuracy of Doppler echocardiography (DE) in the assessment of PASP. The present meta-analysis was performed to estimate the accuracy, sensitivity, and specificity of DE in the assessment of PASP. METHODS: A literature search and data extraction of English and non-English articles reported from May 1984 to January 2009 was performed independently by 2 investigators using MEDLINE and EMBASE databases. Articles were included if they compared DE with right heart catheterization (RHC) in the assessment of PASP. Nine articles met our criteria and were included in our meta-analysis. We conducted a meta-analysis of the results of these articles using fixed- and random-effect models to estimate the accuracy, sensitivity, and specificity of DE in the assessment of PASP. RESULTS: The correlation between PASP estimated by DE and RHC ranged from (r = 0.65, P < 0.001) to (r = 0.97, P < 0.001). The pooled sensitivity, specificity, and accuracy of DE for the diagnosis of PH were 88% (95% confidence interval [CI], 84-92%), 56% (95% CI, 46-66%), and 63% (95% CI, 53-73%), respectively. CONCLUSION: DE is a useful noninvasive modality to screen for PH and can reliably determine whether PASP is normal, mildly elevated, or markedly elevated. However, abnormal results from DE need to be confirmed by RHC.

A practical approach to echocardiographic assessment of perioperative diastolic dysfunction.

The Doppler assessment of diastolic dysfunction (DD) is not part of a standard comprehensive intraoperative echocardiographic examination. Although the reasons may be many, the lack of a simplified algorithm for the assessment of DD specific to the perioperative arena, the implications of this diagnosis on clinical care, and the absence of therapeutic options are some of the commonly cited reasons. In this article, the authors address these possible reasons for the lack of routine application of Doppler indices to assess perioperative DD. The authors have chosen to highlight some of the most common conceptual questions, which often have been raised by anesthesiologists, and attempted to suggest answers. Drawing from their experience and data, the authors propose a simplified algorithm for the application of Doppler to assess and diagnose DD with an individualized and a mechanistic approach. The proposed algorithm is from within the premise of the published guidelines and attempts to simplify the perioperative approach. The authors hope this approach will be simple enough for routine application to affect therapy and a tangible change in outcome. The authors suggest that knowledge of left atrial size is valuable as a marker for persistently increased left ventricular end-diastolic pressure and its possible role in risk stratification.

Longitudinal peak strain detects a smaller risk area than visual assessment of wall motion in acute myocardial infarction.

BACKGROUND: Opening of an occluded infarct related artery reduces infarct size and improves survival in acute ST-elevation myocardial infarction (STEMI). In this study we performed tissue Doppler analysis (peak strain, displacement, mitral annular movement (MAM)) and compared with visual assessment for the study of the correlation of measurements of global, regional and segmental function with final infarct size and transmurality. In addition, myocardial risk area was determined and a prediction sought for the development of infarct transmurality >or=50%. METHODS: Twenty six patients with STEMI submitted for primary percutaneous coronary intervention (PCI) were examined with echocardiography on the catheterization table. Four to eight weeks later repeat echocardiography was performed for reassessment of function and magnetic resonance imaging for the determination of final infarct size and transmurality. RESULTS: On a global level, wall motion score index (WMSI), ejection fraction (EF), strain, and displacement all showed significant differences (p or=50%, but strain added no significant information to that obtained with WMSI in a logistic regression analysis. CONCLUSIONS: In patients with acute STEMI, WMSI, EF, strain, and displacement showed significant changes between the pre- and post PCI exam. In a ROC-analysis, strain had 64% sensitivity at 80% specificity and WMSI around 90% sensitivity at 80% specificity for the detection of scar with transmurality >or=50% at follow-up.

Assessment of the clinical utility of an ultrasonic monitor of cardiac output (the USCOM) and agreement with thermodilution measurement.

OBJECTIVE: To assess the clinical utility of an ultrasonic monitor of cardiac output (USCOM), its reliability in tracking cardiac output (CO) changes and agreement with thermodilution (TD) measurements of CO. DESIGN: Prospective comparison study. SETTING AND PARTICIPANTS: 55 adults undergoing thermodilution (TD) CO monitoring in a cardiothoracic or general intensive care unit between December 2006 and December 2007. MAIN OUTCOME MEASURES: USCOM and TD measurements of CO on two occasions in each patient were compared by Bland-Altman analysis for bias and limit of agreement. A mean percentage error <30% was considered acceptable. Per cent change in cardiac index (CI) was determined by each method. Doppler profiles obtained by the USCOM were assessed against an ideal standard ("acceptable"). RESULTS: 55 patients had measurements on 110 occasions, but Doppler waveforms were not obtained on 18 of these (16%), leaving 39 patients with paired comparisons for analysis (including 27 men; mean age, 64.7 [SD, 14.5] years). Mean TD CI was 3.4 +/-1.0L/min/m(2) (range, 2.0-6.0L/min/m(2)). The bias was 0.6L/min/m(2) (95% confidence limits [CLs], 0.4-0.8 L/min/m(2)), and the mean percentage error was 56% (95% CLs, 45%-65%). Twenty-two Doppler profiles (28%) were classed as acceptable; the mean percentage error for these was 62% (95% CLs, 38%-65%). On 15/19 occasions (74%) where TD CI changed > 15%, USCOM CI also changed >15%, but three of these changes (16%) were in the opposite direction. USCOM CI changed >15% on 9/20 occasions (45%) when TD CI did not. CONCLUSIONS: Poor agreement with TD and a substantial rate of failure to obtain an USCOM measurement suggest that this device is unsuitable as a monitoring tool in intensive care.

A new 2D-based method for myocardial velocity strain and strain rate quantification in a normal adult and paediatric population: assessment of reference values.

BACKGROUND: Recent advances in technology have provided the opportunity for off-line analysis of digital video-clips of two-dimensional (2-D) echocardiographic images. Commercially available software that follows the motion of cardiac structures during cardiac cycle computes both regional and global velocity, strain, and strain rate (SR). The present study aims to evaluate the clinical applicability of the software based on the tracking algorithm feature (studied for cardiology purposes) and to derive the reference values for longitudinal and circumferential strain and SR of the left ventricle in a normal population of children and young adults. METHODS: 45 healthy volunteers (30 adults: 19 male, 11 female, mean age 37 +/- 6 years; 15 children: 8 male, 7 female, mean age 8 +/- 2 years) underwent transthoracic echocardiographic examination; 2D cine-loops recordings of apical 4-four 4-chamber (4C) and 2-chamber (2C) views and short axis views were stored for off-line analysis. Computer analyses were performed using specific software relying on the algorithm of optical flow analysis, specifically designed to track the endocardial border, installed on a Windows based computer workstation. Inter and intra-observer variability was assessed. RESULTS: The feasibility of measurements obtained with tissue tracking system was higher in apical view (100% for systolic events; 64% for diastolic events) than in short axis view (70% for systolic events; 52% for diastolic events). Longitudinal systolic velocity decreased from base to apex in all subjects (5.22 +/- 1.01 vs. 1.20 +/- 0.88; p < 0.0001). Longitudinal strain and SR significantly increased from base to apex in all subjects (-12.95 +/- 6.79 vs. -14.87 +/- 6.78; p = 0.002; -0.72 +/- 0.39 vs. -0.94 +/- 0.48, p = 0.0001, respectively). Similarly, circumferential strain and SR increased from base to apex (-21.32 +/- 5.15 vs. -27.02 +/- 5.88, p = 0.002; -1.51 +/- 0.37 vs. -1.95 +/- 0.57, p = 0.003, respectively). Values of global systolic SR, both longitudinal and circumferential, were significantly higher in children than in adults (-1.3 +/- 0.2, vs. -1.11 +/- 0.2, p = 0.006; -1.9 +/- 0.6 vs. -1.6 +/- 0.5, p = 0.0265, respectively). No significant differences in longitudinal and circumferential systolic velocities were identified for any segment when comparing adults with children. CONCLUSION: This 2D based tissue tracking system used for computation is reliable and applicable in adults and children particularly for systolic events. Measured with this technology, we have established reference values for myocardial velocity, Strain and SR for both young adults and children.

[The "Appropriatezza ECO Milano" project. Assessment of appropriateness of indications, prescriptions and clinical utility of two-dimensional Doppler echocardiography among inpatients and outpatients of Milan, Italy]. / Progetto "Appropriatezza ECO Milano". Valutazione basale dell'appropriatezza delle indicazioni, della modalità delle prescrizioni e dell'utilità clinica dell'esame ecocardiografico bidimensionale color Doppler all'interno delle aziende ospedaliere e sul territorio.

BACKGROUND: The value of echocardiography in the diagnosis and follow-up of most cardiovascular diseases is well established, even though the ever-increasing demand for the use of this technique is not always justifiable. The "Appropriatezza ECO Milano" project was developed among hospitals in Milan (Italy) to foster a rational use of echocardiography. The aim of this study was to evaluate and improve appropriateness of requests for two-dimensional color Doppler echocardiography, considering indications, prescription behaviors and clinical utility in both the outpatient and inpatient settings. METHODS: Following several meetings, a consensus was reached whereby a multicenter, observational study would be undertaken. We assessed the value of each request in agreement with the 2003 American College of Cardiology/American Heart Association/American Society of Echocardiography guidelines. An ad hoc Microsoft Access database was developed to collect study data, which refer to May 2007. Eleven hospitals participated in the study. RESULTS: 4130 echocardiographic examinations were considered (2300 performed in men and 1830 performed in women; mean age 64 +/- 16 years); 1701 examinations were performed in hospitalized patients and 2429 in outpatients. The incidence of pathological findings was higher in hospitalized patients (73%) than in outpatients (53%) (Pearson chi2 = 29, p<0.001). A higher additional clinical value was found in hospitalized vs non-hospitalized patients (48 vs. 35%, Pearson chi2 = 99; p <0.001). In both settings, the majority of echocardiographic examinations were requested by cardiologists (inpatients 36%, outpatients 54%). The most appropriate examinations were performed more frequently in class I or class IIA hospitalized patients (73%) than in outpatients (52%) (Pearson chi2 = 277, p<0.001). Furthermore, the least accurate the indication, the less the clinical utility found in examinations requested from hospitals and outpatient clinics (64 vs 61% in class I patients, Pearson chi2 = 413, p<0.001; 5 vs 11% in class III patients, Pearson chi2 = 584, p<0.001). Conclusions. Our data confirm an inadequate level of appropriateness of requests for two-dimensional color Doppler examinations in either inpatients or outpatients. After over 10 years of passively observing and recording this trend, a timely resolution of these issues is topical in order to improve the implementation of criteria and to guarantee cost-effective and high-quality cardiovascular care.

[Assessment of the reasons prompting a first echocardiography in children: a Lebanese multicenter study]. / Motifs de demande d'une première echocardiographie en pédiatrie: expérience multicentrique Libanaise.

OBJECTIVES: To study the different indications behind performance of a first Doppler echocardiography (DE) in children, to assess the results and their impact on the residency teaching program in Lebanon. MATERIAL AND METHODS: Retrospective study over a 40-month period, from March 1st, 2002, through June 30, 2005. Patients referred for the first DE were examined in different medical centers in Beirut, Mount-Lebanon and South Lebanon. RESULTS: 3137 new patients aged from 0 to 18 years (average: 54 months) were included in the analysis. The percentage of patients seen as outpatients was 48% ; in departments of pediatrics and emergency rooms: 38.2%; intensive care neonatal units: 13%; and in maternity wards/nurseries: 0.8%. 2198 patients (70.1%) had normal DE. Heart murmur accounts for 45.6% of DE requests, followed by extracardiac malformations and presence of dysmorphic features (7.2%), cyanosis (6.8%), suspicion of rheumatic fever (5.7%), cardiac arrhythmia (3.8%), bronchopneumopathies and respiratory distress (3.5%), chest pain and palpitations (3.3%). Innocent murmur was found in 53.9% of patients referred for heart murmur; among syndromes and malformations, Down's syndrome was the most frequent pathology, followed by polymalformations, the VACTERL syndrome and the cleft lip and palate. Cyanotic congenital heart disease was diagnosed in 34% of cases referred for cyanosis. The diagnosis of carditis was confirmed in 84.6% of children with clinical picture of rheumatic fever. In cases of malaise, dizziness and loss of consciousness, no abnormality was detected on DE. CONCLUSION: DE should be a complement to clinical exam, which is often sufficient to reveal a cardiac pathology. However, some conditions, where cardiovascular exam is normal require a DE. The question of when and why to request a DE must be a priority in the pediatric resident training program.

A comparison of cardiologist and noncardiologist use of echocardiograms: implications for containing health care costs.

Echocardiography enables physicians to examine the heart noninvasively and provides a comprehensive evaluation of the cardiovascular system. However, because it is a relatively expensive procedure compared to an ECG or X-ray, it is crucial that "echo" be utilized appropriately and judiciously. Using a retrospective chart review, we sought to determine whether there are differences in concordance between the diagnoses and echo findings of cardiologists and those of other physicians. Due to cardiologists' greater knowledge of cardiophysiology and echocardiography, cardiologists were expected to have a higher concordance between patient diagnosis and echocardiogram findings when compared to noncardiology physicians. Randomly, 500 echo reports were assessed for diagnosis, reason for the echo, and whether the echo findings agreed with the diagnosis. Other criteria that were studied included whether there were additional, unanticipated findings and whether these findings were of major or minor importance. Concordance between cardiologist pre-test diagnosis and echo findings was found in 95 out of 175 tests (54%). Noncardiologist pre-test diagnosis concordance with echo findings was found in 117 out of 325 tests (36%) (p<0.0001). Thus, the c ardiologists were found to have a significantly higher concordance between diagnosis and findings on echocardiogram when compared to noncardiologist physicians.

[Assessment of myocardial performance in fetuses by using Tei index].

OBJECTIVE: To define the value of Tei index of normal fetuses and to estimate the influence of gestational week and heart rate on the index. METHODS: Fetal echocardiograms were performed on 225 normal single fetuses, which were divided into three groups (18 approximately 27(+6), 28 approximately 36(+6), 37 approximately 42 gestational weeks). The Tei indexes of both left and right ventricles (LV and RV) were measured by color Doppler ultrasonography. t test was used to compare the Tei index between LV and RV. The correlation between Tei index, gestational week and fetal heart rate were analyzed. RESULTS: The Tei indexes in three different gestational week groups (18 approximately 27(+6), 28 approximately 36(+6), 37 approximately 42 gestational weeks) were 0.37 +/- 0.08, 0.27 +/- 0.05, 0.22 +/- 0.05 of LV and 0.39 +/- 0.04, 0.30 +/- 0.05, 0.24 +/- 0.04 of RV respectively. There was significant difference of Tei index of RV and LV during 28 approximately 36(+6) gestational weeks (P < 0.05). The Tei index of LV and RV decreased linearly with advancing gestational week during 18 - 42 weeks (LV: r = -0.755, PP < 0.05; RV: r = -0.721, P < 0.05) in normal single fetuses. None of the fetal Tei indexes of LV and RV was related to fetal heart rate (LV: r = 0.133, P > 0.05; RV: r = 0.100, P > 0.05). CONCLUSION: Tei index may be useful, convenient and reliable in fetal cardiac function assessment.

Assessment of mitral annular velocities by Doppler tissue imaging in predicting left ventricular thrombus formation after first anterior acute myocardial infarction.

The aim of this study was to determine whether early assessment of left ventricular (LV) systolic and diastolic functions by pulsed wave Doppler tissue imaging predicts LV thrombus formation after acute anterior myocardial infarction. Echocardiography was performed in 87 consecutive patients with first acute anterior myocardial infarction within 24 hours after arrival to the coronary care department. Mitral inflow velocities and early diastolic (Em), late diastolic (Am), and peak systolic (SM) mitral annular velocities were measured. Em/Am and the ratio of early diastolic mitral inflow velocity to Em (E/Em), which is a reasonably good index for predicting elevated LV filling pressure, were calculated. To detect LV thrombus, 2-dimensional echocardiography was repeated on days 3, 7, 15, and 30. Patients were divided into two groups according to LV thrombus formation: group 1 (n = 29; aged 59 +/- 11 years; 4 women) with thrombus; and group 2 (n = 58; aged 57 +/- 9 years; 6 women) without thrombus. Members of group 1 had significantly lower Em, a lower SM, a lower peak systolic mitral annular velocity, and a lower Em/Am than those in group 2 (6.4 +/- 2.0 cm/s vs 8.9 +/- 2.7 cm/s, P < .001; 7.3 +/- 1.6 cm/s vs 8.6 +/- 1.7 cm/s, P = .001; 0.65 +/- 0.25 cm/s vs 0.89 +/- 0.27 cm/s, P < .001, respectively). The E/Em was significantly higher in group 1 than in group 2 (12.5 +/- 5.0 vs 7.2 +/- 2.8, P < .001). The sensitivity of an E/Em ratio greater than 9 in predicting LV thrombus formation was 69%, the specificity 79%, the positive predictive value 63%, and the negative predictive value 84%. Mitral annular velocities derived by pulsed wave Doppler tissue imaging are simple to obtain even in technically suboptimal studies, and can be used for predicting LV thrombus formation after myocardial infarction.

Contribution of Doppler tissue imaging and myocardial performance index to assessment of left ventricular function in patients with Duchenne's muscular dystrophy.

Doppler tissue velocities (DTV) are abnormal in a variety of cardiac conditions when standard measures of ventricular function are normal. Detection of left ventricular dysfunction in Duchenne's muscular dystrophy (DMD) has relied on 2-dimensional imaging yet often these images are suboptimal. This study was undertaken to determine if DTV and the myocardial performance index (MPI) could provide additional diagnostic information in DMD. We determined in 31 patients and 13 age-matched control subjects the prevalence of both abnormal DTV of the mitral annulus and abnormal MPI. Mean values for early diastolic DTV were significantly lower for patients compared with control subjects (P < .001) and were abnormally low in 86% of patients. The MPI was abnormal in 79% of patients. All but one patient with DMD had either abnormal DTV or abnormal MPI yet 19% had normal fractional shortening. DTV and MPI are important additions to the echocardiographic evaluation of patients with DMD.

Noninvasive assessment of mitral inertness [correction of inertance]: clinical results with numerical model validation.

Inertial forces (Mdv/dt) are a significant component of transmitral flow, but cannot be measured with Doppler echo. We validated a method of estimating Mdv/dt. Ten patients had a dual sensor transmitral (TM) catheter placed during cardiac surgery. Doppler and 2D echo was performed while acquiring LA and LV pressures. Mdv/dt was determined from the Bernoulli equation using Doppler velocities and TM gradients. Results were compared with numerical modeling. TM gradients (range: 1.04-14.24 mmHg) consisted of 74.0 +/- 11.0% inertial forcers (range: 0.6-12.9 mmHg). Multivariate analysis predicted Mdv/dt = -4.171(S/D (RATIO)) + 0.063(LAvolume-max) + 5. Using this equation, a strong relationship was obtained for the clinical dataset (y=0.98x - 0.045, r=0.90) and the results of numerical modeling (y=0.96x - 0.16, r=0.84). TM gradients are mainly inertial and, as validated by modeling, can be estimated with echocardiography.

Assessment of left ventricular systolic function in patients with idiopathic mitral valve prolapse using dobutamine stress echocardiography.

BACKGROUND: Some previous studies performed with radionuclide ventriculography and thallium scintigraphy reported that patients with idiopathic mitral valve prolapse (MVP) had some degree of left ventricular (LV) systolic dysfunction and that this dysfunction was more commonly found in symptomatic patients. HYPOTHESIS: The aim of the present prospective study was to investigate LV systolic function and its relationship with symptoms in patients with MVP with dobutamine stress test without associated certain mitral regurgitation and coronary artery disease. METHODS: Thirty-three patients with echocardiographically diagnosed idiopathic MVP were enrolled into the study and were divided into two groups as symptomatic (MVP-s) and asymptomatic (MVP-a). Patients underwent dobutamine stress echocardiography (DSE) to determine wall motion abnormalities and ejection fraction (EF) changes during rest state and increased heart rates. Results were compared with the DSE findings of 25 healthy individuals. RESULTS: Symptomatic patients (MVP-s) had lower EFs during the pretest period than the control group (59.0 +/- 4.8% and 68.3 +/- 5.7%, respectively, p < 0.05). Basal wall motion abnormalities were found in one patient in the MVP-a group (6%) and in two patients in the MVP-s group (12%). During DSE, new wall motion abnormalities (inferoapical dyskinesia) occurred in two patients in the MVP-s group at submaximal heart rates. For EF values calculated when patients reached submaximal heart rate, the MVP-s group showed only a 2.7 +/- 3.1% increase from baseline values. This increase was 5.1 +/- 3.8% in the MVP-a group and 9.3 +/- 4.3% in the control group (p < 0.05 between MVP-s and control groups). CONCLUSION: There is a close relationship between symptoms and ventricular function in patients with idiopathic MVP, and although many asymptomatic patients had nearly normal LV function, a subgroup of symptomatic patients showed diminished LV function and wall motion abnormalities.

Assessment of myocardial perfusion by harmonic power Doppler imaging at rest and during adenosine stress: comparison with (99m)Tc-sestamibi SPECT imaging.

BACKGROUND: Harmonic power Doppler imaging (HPDI) is a novel technique for assessing myocardial perfusion by contrast echocardiography in humans. The purpose of this study was to compare myocardial perfusion by HPDI with that obtained by (99m)Tc-sestamibi single photon emission computed tomography (SPECT) during rest and pharmacological stress. METHODS AND RESULTS: HPDI was performed on 123 patients who were referred for SPECT imaging for known or suspected coronary artery disease. Images were obtained at baseline and during adenosine infusion (0.14 mg. kg(-)(1). min(-)(1)x6 minutes) in 3 apical views. Myocardial perfusion by HPDI was graded for each coronary territory as absent, patchy, or full. The persistence of absent or patchy myocardial perfusion by HPDI between rest and adenosine was interpreted as a fixed defect, whereas any decrease in perfusion grade was interpreted as a reversible defect. Overall concordance between HPDI and SPECT was 83 (81%) of 103 for normal versus abnormal perfusion. Agreement between the 2 methods for each of the 3 coronary territories was 81% (kappa=0.57) for the left anterior descending artery, 76% (kappa=0.52) for the right coronary artery, and 72% (kappa=0.40) for the left circumflex artery. Discrepancies between the 2 techniques were most notable in the circumflex territory, where fixed defects were observed in 33% by HPDI but in only 14% by SPECT (chi(2)=15.8, P=0.0001). CONCLUSIONS: This study demonstrates that HPDI can reliably detect myocardial perfusion during pharmacological stress, although there was a significantly higher number of falsely abnormal results in the circumflex territory.

Noninvasive assessment of left atrial maximum dP/dt by a combination of transmitral and pulmonary venous flow.

OBJECTIVES: The study assessed whether hemodynamic parameters of left atrial (LA) systolic function could be estimated noninvasively using Doppler echocardiography. BACKGROUND: Left atrial systolic function is an important aspect of cardiac function. Doppler echocardiography can measure changes in LA volume, but has not been shown to relate to hemodynamic parameters such as the maximal value of the first derivative of the pressure (LA dP/dt(max)). METHODS: Eighteen patients in sinus rhythm were studied immediately before and after open heart surgery using simultaneous LA pressure measurements and intraoperative transesophageal echocardiography. Left atrial pressure was measured with a micromanometer catheter, and LA dP/dt(max) during atrial contraction was obtained. Transmitral and pulmonary venous flow were recorded by pulsed Doppler echocardiography. Peak velocity, and mean acceleration and deceleration, and the time-velocity integral of each flow during atrial contraction was measured. The initial eight patients served as the study group to derive a multilinear regression equation to estimate LA dP/dt(max) from Doppler parameters, and the latter 10 patients served as the test group to validate the equation. A previously validated numeric model was used to confirm these results. RESULTS: In the study group, LA dP/dt(max) showed a linear relation with LA pressure before atrial contraction (r = 0.80, p < 0.005), confirming the presence of the Frank-Starling mechanism in the LA. Among transmitral flow parameters, mean acceleration showed the strongest correlation with LA dP/dt(max) (r = 0.78, p < 0.001). Among pulmonary venous flow parameters, no single parameter was sufficient to estimate LA dP/dt(max) with an r2 > 0.30. By stepwise and multiple linear regression analysis, LA dP/dt(max) was best described as follows: LA dP/dt(max) = 0.1 M-AC +/- 1.8 P-V - 4.1; r = 0.88, p < 0.0001, where M-AC is the mean acceleration of transmitral flow and P-V is the peak velocity of pulmonary venous flow during atrial contraction. This equation was tested in the latter 10 patients of the test group. Predicted and measured LA dP/dt(max) correlated well (r = 0.90, p < 0.0001). Numerical simulation verified that this relationship held across a wide range of atrial elastance, ventricular relaxation and systolic function, with LA dP/dt(max) predicted by the above equation with r = 0.94. CONCLUSIONS: A combination of transmitral and pulmonary venous flow parameters can provide a hemodynamic assessment of LA systolic function.

[The Doppler echocardiographic assessment of left ventricular diastolic function in coronary heart disease]. / Dopplerechokardiographische Beurteilung der diastolischen linksventrikulären Funktion bei koronarer Herzkrankheit.

BACKGROUND AND OBJECTIVE: Changes in left ventricular (LV) diastolic function lead to characteristic changes in the transmitral flow profile as determined by Doppler echocardiography (DEC). Although DEC cannot provide direct quantitative measurement of LV filling pressures and is influenced by several factors, transmitral flow correlates well with LV haemodynamics. In this prospective study the results of transthoracic DEC were compared with haemodynamic parameters in patients with coronary heart disease (CHD) and their clinical value assessed. PATIENTS AND METHODS: 254 consecutive patients with CHD (67 women, 187 men, aged 62.5 +/- 8.5 years) underwent transthoracic DEC. The ratio of early to late diastolic velocity (VE/VA) and early diastolic deceleration time (DT) of the transmitral flow were measured as an indication of diastolic LV function. RESULTS: Patients with reduced LV compliance and increased filling pressure (LV end-diastolic pressure [LVEDP] > 15 mm hg) had a restrictive transmitral flow profile with a significantly higher than normal VE/VA and a shorter DT (1.35 +/- 0.84 vs. 0.86 +/- 0.26, P < 0.001; and 158 +/- 45 vs. 213 +/- 35, P < 0.001, respectively). VE/VA and DT also significantly correlated with LVEDP (r = 0.65, P < 0.001 and r = -0.60, P < 0.001 respectively). Sensitivity and specificity of an LVEDP of > 15 mm Hg were 67% and 84%, respectively, for a VE/VA of more than 1, and 65% and 91% for a DT of less than 170. The combination of the two parameters increased specificity to 97%. CONCLUSION: Determining the transmitral flow profile makes it possible noninvasively to obtain an indication of LV end-diastolic function. Patients with severe diastolic dysfunction and increased filling pressures are recognized with a high degree of specificity.

Doppler echocardiographic assessment of prosthetic aortic valve area: estimation with the continuity equation compared to the Gorlin formula.

Effective orifice area of 3 different designs of prosthetic valves implanted in the aortic position was determined by the continuity equation and the Gorlin formula using Doppler hemodynamic data. The orifice area by the two methods correlated well in the case of tilting disc prostheses (r = 0.75, P = 0.0001, n = 37, SEE = 0.17 cm2) but poorly in the case of bileaflet mechanical valves (r = 0.40, P = 0.17, n = 13) and ball-in-cage prostheses (r = 0.58, P = 0.06, n = 11). Estimation of prosthetic aortic valve area by the Gorlin formula is inappropriate in the latter two types of prostheses because of design-related variable empiric constant.