Simultaneous detection and identification of the Xanthomonas species complex associated with tomato bacterial spot using species-specific primers and multiplex PCR.

AIMS: To establish protocols for the simultaneous detection and identification of Xanthomonas species causing tomato bacterial spot. METHODS AND RESULTS: We verified the specificity and sensitivity of the previously reported sets of primers designed for strains of the four species of Brazilian tomato bacterial spot xanthomonads, consisting of 30 of Xanthomonas euvesicatoria, 30 of X. vesicatoria, 50 of X. perforans and 50 of X. gardneri. Furthermore, we tested a multiplex PCR protocol for the purpose of concurrent species identification. The possibility of direct detection of the pathogens in diseased leaf samples was also verified. The primers were highly specific, amplifying only target DNA. The sensitivity of the primers in conventional PCR was 50 pg µl(-1) for purified DNA and ranged from 5 × 10(2) to 5 × 10(4) CFU ml(-1) when bacterial suspensions were analysed. The multiplex PCR was suitable for the detection of all four species and showed similar sensitivity to conventional PCR when tested on purified DNA. When using bacterial suspensions, its sensitivity was similar to conventional PCR only when a biological amplification step (Bio-PCR) was included. Both methods were able to detect the pathogens in symptomatic tomato leaves. CONCLUSIONS: Brazilian Xanthomonas strains causing tomato bacterial spot can be differentiated and identified at species level by a PCR-based method and by a multiplex PCR. SIGNIFICANCE AND IMPACT OF THE STUDY: This protocol may be a feasible alternative tool for the identification and detection of these pathogens in plant material and may be used for routine diagnostic purposes in plant pathology laboratories.

New hosts of Myrothecium spp. in Brazil and a preliminary in vitro assay of fungicides

Myrothecium roridum and M. verrucaria are two plant pathogenic species causing foliar spots in a large number of cultivated plants. This paper aims to study the causal agents of foliar spots in vegetable crops (sweet pepper, tomato and cucumber), ornamental plants (Spathiphyllum wallisii, Solidago canadensis, Anthurium andreanum, Dieffenbachia amoena) and a solanaceous weed plant (Nicandra physaloides). Most of the isolates were identified as M. roridum; only the isolate 'Myr-02' from S. canadensis was identified as M. verrucaria. All the isolates were pathogenic to their original plant hosts and also to some other plants. Some fungicides were tested in vitro against an isolate of M. roridum and the mycelial growth recorded after seven days. Fungicides with quartenary ammonium, tebuconazole and copper were highly effective in inhibiting the mycelial growth of M. roridum. This paper confirms the first record of M. roridum causing leaf spots in sweet pepper, tomato, Spathiphyllum, Anthurium, Dieffenbachia and N. physaloides in Brazil. We also report M. roridum as causal agent of cucumber fruit rot and M. verrucaria as a pathogen of tango plants.

New hosts of Myrothecium SPP. In brazil and a preliminary In Vitro assay of fungicides.

Myrothecium roridum and M. verrucaria are two plant pathogenic species causing foliar spots in a large number of cultivated plants. This paper aims to study the causal agents of foliar spots in vegetable crops (sweet pepper, tomato, cucumber), ornamental plants (Spathiphyllum, Solidago canadensis, Anthurium, Dieffenbachia) and a solanaceous weed plant (Nicandra physalodes). Most of the isolates were identified as M. roridum; only the isolate 'Myr-02' from S. canadensis was identified as M. verrucaria. All the isolates were pathogenic to their original plant hosts and also to some other plants. Some fungicides were tested in vitro against an isolate of M. roridum and the mycelial growth recorded after seven days. Fungicides with quartenary ammonium, Tebuconzole and copper were highly effective in inhibiting the mycelial growth of M. roridum. This paper confirms the first record of M. roridum causing leaf spots in sweet pepper, tomato, Spathiphyllum, Anthurium, Dieffenbachia and N. physalodes. We also report M. roridum as causal agent of cucumber fruit rot and also M. verrucaria in tango plants.

Stratification of single-vessel coronary stenosis by ischemic threshold at the onset of wall motion abnormality during continuous monitoring of left ventricular function by semisupine exercise echocardiography.

We studied the relation between the ischemic threshold at the onset of wall motion abnormality on exercise echocardiography (EE) and the severity of coronary stenosis in patients with 1-vessel coronary artery disease (CAD). We screened 216 consecutive patients who underwent coronary angiography and EE for suspected CAD. Ninety-five (74 men; age, 56 +/- 12 years) satisfied the study criteria, that is, the presence of 1-vessel disease or no evidence of CAD on angiography and a normal baseline echocardiogram. Eighty-seven patients had 1-vessel CAD on angiography, and exercise-induced wall motion abnormality occurred in 73 (77%). Optimal cutoff values of percent diameter stenosis and minimal lumen diameter for predicting a positive EE were 61% (sensitivity and specificity of 76%) and 1.12 mm (sensitivity and specificity of 74%). Among patients with positive EE, heart rate-blood pressure product at ischemic threshold was correlated with quantitative coronary stenosis (r = -0.72, P <.001). The ischemic threshold from continuous monitoring of left ventricular function during semisupine EE is correlated with the severity of coronary stenosis among patients with 1-vessel disease and a normal resting echocardiogram.

[Chronic ischemic left ventricular dysfunction: myocardial hibernation?]. / Dysfonction ventriculaire gauche chronique d'origine ischémique: hibernation myocardique?

Hibernating myocardium is a term which covers chronic ischaemic left ventricular dysfunction which is potentially reversible after revascularisation. Hibernating myocardium is classically associated with chronic hypoperfusion responsible for hypocontraction and cellular degeneration. This "classical" conception has been questioned as some workers emphasise that the reduction in coronary reserve responsible for repeated episodes of ischaemia and stunning could be the main causes of myocardial dysfunction. Position emission tomography (PET), and, most of all, myocardial scintigraphy and dobutamine echocardiography are the most commonly used techniques for detecting hibernating myocardium. Their sensitivity is good but the specificity and positive predictive value of dobutamine echocardiography seems to be better than the isotopic techniques. Structural abnormalities of hibernating myocardium and the delay, which is often long, between revascularisation and improvement, may explain some of the discordances between these techniques. Irrespective of the term used, hibernation or chronic ischaemic left ventricular dysfunction with myocardial viability, the reported data is in favour of coronary revascularisation with improved long-term quality of life and reduced mortality in patients with positive viability tests.

[The best of echocardiography in 1999]. / L'essentiel de 1999 en échocardiographie.

As many techniques of medical investigation, echocardiography regularly benefits from technical innovations which, with application, prove to be extremely useful and, for some of them, even widen the field of investigation. The end of this decade has seen the introduction of major improvements. In daily practice, second harmonic imaging has been the most important technical advance with such improved quality of imaging that this mode has rapidly become the routine for transthoracic investigations in adults. All modern echocardiographs are, or can be, equipped at modest cost. Stress echocardiography, the diagnostic reliability of which is closely related to the quality of the imaging, has greatly benefited from this technique, to the point of obtaining equivalent results as nuclear medicine in the detection of myocardial ischaemia and cellular viability. The results are now sufficiently convincing for the technique to have a real prognostic value in myocardial ischaemia. Doppler tissue imaging is also a major advance but the clinical value is still under evaluation: the pulsed Doppler mode is quantifiable during the investigation, contrary to the calculation of transparietal velocity gradients which requires computerisation techniques not provided by all manufacturers. The regain in interest in contrast echocardiography is due to the development of agents which, injected intravenously, cross the pulmonary capillary barrier and opacify the left heart chambers. The reinforcement of the Doppler signal and improved detection of the endocardial echoes have justified the authorization of their commercialisation, but the essential point is their use in the investigation of myocardial perfusion which is under evaluation. Three-dimensional reconstruction has made great strides but its diffusion is still limited by the limited availability of the required powerful computers.

The new drugs (chlorpromazine & reserpine): administrative aspects. 1956.

The article on the new drugs reprinted below appeared in the February 1956 issue of Mental Hospitals. It is based on a discussion held during the Seventh Mental Hospital Institute in October 1955 in Washington, D.C. Chlorpromazine and reserpine had been available in the United States less than two years when the institute participants met to discuss how their hospitals were coping with the demands of the new treatments. In a commentary and analysis beginning on page 333, Robert Cancro, M.D., considers the broader impact of the introduction of neuroleptics and examines the concerns of the 1956 institute participants in the context of today.

Prognostic value of MIBG imaging in idiopathic dilated cardiomyopathy.

UNLABELLED: Alterations of cardiac sympathetic innervation are likely to contribute to fatal outcomes in patients with heart failure. These alterations can be evaluated noninvasively by 123I-metaiodoben-zylguanidine (MIBG) imaging. METHODS: The hypothesis that impaired cardiac sympathetic innervation, as assessed using MIBG imaging, is related to adverse outcomes was tested in 112 patients with heart failure resulting from idiopathic cardiomyopathy. Main inclusion criteria were New York Heart Association classes II-IV and radionuclide left ventricular ejection fraction (LVEF) < 40%. Patients were assessed for cardiac MIBG uptake, circulating norepinephrine concentration, LVEF, peak Vo2, x-ray cardiothoracic ratio, M-mode echographic end-diastolic diameter and right-sided heart catheterization parameters. RESULTS: During a mean follow-up of 27 +/- 20 mo, 19 patients had transplants, 25 died of cardiac death (8 sudden deaths), 2 died of noncardiac death and 66 survived without transplantation. The only independent predictors for mortality were low MIBG uptake (P < 0.001) and LVEF (P = 0.02) when using multivariate discriminant analysis. Moreover, MIBG uptake (P < 0.001) and circulating norepinephrine concentration (P = 0.001) were the only independent predictors for life duration when using multivariate life table analysis. CONCLUSION: Impaired cardiac adrenergic innervation as assessed by MIBG imaging is strongly related to mortality. MIBG imaging may help risk stratify patients with heart failure resulting from idiopathic dilated cardiomyopathy.

[Hypertrophic obstructive cardiomyopathy and double-chamber pacing. Long-term results in a consecutive series of 22 patients]. / Cardiomyopathie hypertrophique obstructive et stimulation cardiaque double chambre. Résultats à long terme d'une série consécutive de 22 patients.

The authors report their experience with dual-chamber pacing in hypertrophy obstructive cardiomyopathy. 22 patients (14 women and 8 men) mean age 60 +/- 13 years were implanted between 1992 and 1998. The criteria for pace-maker implantation were the presence of severe symptoms related with hypertrophy obstructive cardiomyopathy (dyspnea, angina, syncope) and left ventricular outflow tract gradient at mean 30 mmHg. Before pacing, all patients received a medical therapy which included beta-blockers or calcium inhibitors. This treatment was considered as ineffective or responsible of side effects. Patients were followed-up at mean 35.1 +/- 20.3 months. During this period, symptoms improved (mean NYHA class 2.7 +/- 0.5 before pacing vs 1.4 +/- 0.5 after pacing) and left ventricular outflow tract lowered from 95.4 +/- 40.8 to 39.3 +/- 20.5 at 6 months. 34.3 +/- 23.4 at one year and 26.5 +/- 21 at the end of follow-up. Seven patients had RF ablation of atrio-ventricular junction for paroxysmal atrial fibrillation or for lack of hemodynamic improvement with pacing. This procedure permits a significative lowering of gradient and a better ventricular filling. In conclusion, dual-chamber pacing is effective for treatment of hypertrophy obstructive cardiomyopathy when medical therapy is ineffective or bad tolerated at condition of: perfect pacing with permanent ventricular capture and optimal AV delay; RF ablation of AV junction in one third of cases; medical therapy systematically associated in all patients.

[Myocardial viability. Myocardial viability post-infarct: contribution of dobutamine-echography]. / La viabilité myocardique. Viabilité myocardique post-infarctus: place de l'échographie-dobutamine.

ROUTINE EXPLORATION: Echocardiography during dopamine perfusion has been widely proven as an effective tool for determining myocardial viability. Dobutamine has marketing authorization in France for stress-echocardiography and is widely used in clinical practice outside research protocols. The exploration must however be conducted within an appropriately equipped cardiac intensive care unit. Stress-echocardiography has certain advantages over isotropic techniques, in terms of equipment costs, examination time and exposure to isotopes. POST-INFARCTION: Dobutamine-echocardiography enables detection of viable myocardium within the infarct zone, evaluates the degree of residual ischemia in the infarct zone and provides information on prognosis. It would not however be reasonable to perform stress-echocardiography as a first line exploration after infarction. International guidelines recommend a sub-maximal ECG exercise test prior to coronarography. The contribution of stress-echocardiography after infarction is its ability to give precise information on myocardial viability and residual ischemia in one or more territories to compare with coronary lesions, thus allowing indication for revascularization. CHRONIC ISCHEMIC CARDIOPATHY: Dobutamine-echocardiography can be used to detect hibernating myocardium in patients with chronic ischemic cardiopathy. In this indication, the sensitivity of stress-echocardiography is slightly lower than thallium scintigraphy, but its specificity and positive predictive values are higher. The best predictive value is obtained with bimodal dobutamine-echocardiography: improve-med thickening at low doses and a degradation at high dose is predictive of functional improvement after revascularization in 72% of the cases. In more severe cases with ejection fraction < 35%, improvement in hibernating myocardium after revascularization leads to a significant improvement in left ventricular ejection fraction.

Is left atrial appendage flow a predictor for outcome of cardioversion of nonvalvular atrial fibrillation? A transthroacic and transesophageal echocardiographic study.

Accurate echocardiographic parameters for predicting the success of cardioversion or maintenance of sinus rhythm are poorly defined. This prospective transthoracic and transesophageal echocardiographic study was conducted to test the hypothesis that the left atrial appendage flow pattern could be a predictive parameter of the success of cardioversion and maintenance of sinus rhythm in patients with nonvalvular atrial fibrillation. Eighty-two consecutive patients with nonvalvular atrial fibrillation of <6 months' duration underwent transesophageal examination after transthoracic echocardiography. After exclusion of left atrial thrombus, pharmacologic (n = 18) or electrical (n = 64) cardioversion was successful in 75 of 82 patients. In the group that underwent successful cardioversion, maintenance of sinus rhythm (n = 35) or recurrence of arrhythmia (n = 40) was assessed during a 1-year follow-up. During transesophageal examination, five left atrial appendage thrombi were found, spontaneous echo contrast was present in 26 (32%) patients, and mean peak left atrial appendage emptying velocity was 35 +/- 18 cm/sec. Peak left atrial appendage emptying velocity was found to be statistically related to parameters of left ventricular and left atrial function but not to long-term maintenance of sinus rhythm. No other echocardiographic parameter was identified as a predictor for either the success of cardioversion or the maintenance of sinus rhythm at follow-up. In patients with nonvalvular atrial fibrillation of recent onset, peak left atrial appendage emptying velocity appears to be a complex parameter depending on left atrial and left ventricular function but that does not predict either the success rate of cardioversion or long-term maintenance of sinus rhythm after successful cardioversion.

[Echocardiographic factors predicting the maintenance of sinus rhythm one year after cardioversion for non-valvular atrial arrhythmias]. / Facteurs échographiques prédictifs du maintien du rythme sinusal un an après cardioversion pour trouble du rythme auriculaire non valvulaire.

Echocardiographic factors predictive of the maintenance of sinus rhythm after successful cardioversion were investigated in 94 patients with non-valvular atrial arrhythmias of recent onset. Seventy-five patients with atrial fibrillation and 19 with atrial flutter admitted for reduction of their arrhythmias underwent transthoracic and transoesophageal echocardiography. After excluding a thrombus in the left atrial appendage or checking that it had disappeared (5 patients), and electrical (n = 74) or pharmacological (n = 20) cardioversion was successfully performed. The maintenance of sinus rhythm (n = 44) or recurrence of arrhythmia (n = 50) were controlled every 3 months for one year. The mean value of the peak positive blood flow in the left atrial appendage was 38 +/- 20 cm/s for the whole group. It was not possible to identify an echocardiographic parameter predictive of maintenance of sinus rhythm at one year either in the whole group or in the subgroups with atrial flutter or atrial fibrillation. In the group in atrial flutter, the mean value of the peak positive blood flow in the left atrial appendage was significantly greater than in the group with atrial fibrillation: 49 +/- 22 cm/s vs 35 +/- 18 cm/s, respectively; p < 0.05. The peak of positive flow in the left atrial appendage was statistically related to indirect parameters of left atrial function and of left ventricular function in the group with atrial fibrillation but only with parameters of left ventricular function in the smaller group with atrial flutter.

[Cerebral abscess disclosing tetralogy of Fallot with situs inversus in adulthood]. / Abcès cérébral révélant à l'âge adulte une tétralogie de Fallot sur situs inversus.

The authors report the case of tetralogy of Fallot (TOF) associated with situs inversus, the first description of this rare association in a previously asymptomatic adult. A 32 years old chauffeur was admitted to hospital with pyrexia and convulsions due to a left temporo-parietal cerebral abscess which had a favourable outcome. The chest X-ray and Doppler echocardiographic study showed a TOF with a high infundibular stenosis and dextrocardia. Abdominal ultrasonography confirmed a complete situs inversus. The good tolerance was attributed to the equilibrated character of the TOF. The orientation of the heart and the cono-truncal septation occur at different times during embryogenesis. However, there are genetic arguments in favour of the non-fortuitous nature of this association.

Right ventricular late filling termination time and its relation to interstitial collagen content in early transplanted heart: a color M-mode Doppler digital analysis.

BACKGROUND: Histologic changes in cardiac allografts resulting from fibrosis or acute rejection can modify ventricular diastolic function and ventricular inflow characteristics. These abnormalities may be detected by color M-mode Doppler echocardiography which has been shown to be sensitive in assessing ventricular diastolic function. METHODS: Twelve cardiac allograft recipients were prospectively studied with serial color M-mode and single-gated Doppler echocardiography, as well as with endomyocardial biopsy, with a follow-up of approximately 10 weeks. The myocardial interstitial collagen content as evaluated by videodensitometry was compared with right and left ventricular late filling termination times measured in the absence of a severe episode of rejection. RESULTS: A positive and significant correlation was found between the collagen content and the corresponding right ventricular late filling termination time (r = 0.89, p < 0.0001), but no correlation was found with the left ventricular late filling termination time. Moreover, variations in collagen content and variations in right ventricular late filling termination time were also highly correlated (r = 0.91, p < 0.0001). In allograft recipients who had episodes of rejection of grade 3A or greater, both right and left ventricular late filling termination times were significantly increased during rejection. CONCLUSIONS: Measurements of right ventricular late filling termination time by color M-mode Doppler echocardiography performed in the absence of acute rejection can be use to monitor the evolution of interstitial collagen content in cardiac allografts. The early detection of abnormally prolonged late filling termination time could be followed by endomyocardial biopsy to confirm the histologic changes.

[Study of myocardial viability after recent infarction by echocardiography under dobutamine. Evidence of stunned myocardium]. / Etude de la viabilité myocardique après infarctus récent par l'échocardiographie sous dobutamine. Mise en évidence du myocarde sidéré.

After myocardial infarction treated by thrombolysis, secondary improvement of contractility may be observed due to the presence of viable but stunned myocardium in a zone of ischaemia. Echocardiography with lose dose Dobutamine has been proposed as a diagnostic test of myocardial viability. The inotropic effect of the pharmacological agent improves or induces myocardial thickening in zones of ischaemia. A positive response is observed in about one out of two cases. The sensitivity ranges from 79 to 86% and the specificity from 68 to 90% in the reported series. This mode of stress echocardiography for the study of post-infarction myocardial viability is under clinical evaluation: its advantages and limitations should be compared with those of other non-invasive methods, especially thallium myocardial scintigraphy.

[Doppler echocardiographic evaluation of mitral flow velocity and prognosis of cardiac insufficiency]. / Vitesses du flux mitral évaluées en échocardiographie doppler et pronostic de l'insuffisance cardiaque.

The aim of this study was to determine the role of Doppler echocardiography in establishing the prognosis of Stages to 4 cardiac failure. The echocardiographic indices of left ventricular filling were correlated with catheter data and the 2 year out come of patients. The study population included 54 patients examined prospectively in the context of an evaluation of their cardiac failure. Two years after the initial examination, 19 patients were dead or transplanted. Of the remaining 35 patients, 18 were reevaluated at 6 months. Of the echocardiographic parameters, "hyper normal" mitral flow with a high E/A ration indicated poor prognosis; when E/A > 2, the one year survival was 50% and the 2 year survival 42%. There was overlap between the groups of dead or transplanted and surviving patients only when the E/A ratio was between 2 and 3. The patients with E/A < 2 were all alive without any major events at 2 years. All patients with E/A > 3 had a poor prognosis. The E/A ratio was closely correlated with pulmonary capillary pressure levels (p < 0.001, r = 0.55) and lees closely with cardiac index (p < 0.05, r = 0.4) and radionuclide ejection fraction (p < 0.05, r = 0.28). After 6 months' vasodilator treatment with an angiotensin converting enzyme inhibitor (captopril) the E/A ratio decreased significantly from 1.85 +/- 0.78 to 1.0 0.55 (p < 0.02). A "hyper-normal" mitral flow is related to many factors, including high left ventricular filling pressures, mitral regurgitation and reduced left ventricular compliance. This appearance of mitral flow is a poor prognosis factor in severe cardiac failure.

Preservation of the aortic valve in acute aortic dissection: long-term echocardiographic assessment and clinical outcome.

The aim of the present study was to determine the long-term status of the native aortic valve after surgical treatment of acute aortic dissection involving the ascending aorta. From 1972 to 1991, 93 patients underwent operation for type I or II aortic dissection. There were 76 men and 17 women. Mean age was 54 +/- 13 years. Eighty patients (86%) had a conservative procedure regarding the aortic root and aortic cusps: 74 had prosthetic replacement of the ascending aorta and 6, complete replacement of the aortic arch. Thirteen patients (14%) had simultaneous replacement of the aortic valve and the ascending aorta. The overall hospital mortality rate was 29% (27/93). The overall actuarial survival rate was 60.2% +/- 5.2%, 49.7% +/- 6.1%, and 35.9% +/- 8.1% at 5, 10, and 15 years, respectively. The survival rates for patients who had an ascending aortic procedure only were 63% +/- 5.5%, 54% +/- 6.5%, and 39% +/- 8.5% at 5, 10, and 15 years, respectively, and for patients who required aortic valve replacement, 45% +/- 14% and 22% +/- 17.5% at 5 and 10 years, respectively. Fifty long-term survivors (94% follow-up) with preservation of the aortic valve and aortic root were studied. Among them, 9 (18%) died within a mean interval of 97 +/- 46 months after operation. Causes of death were ischemic cardiac failure (2), aortic rupture or extension of dissection (4), renal disease (1), stroke (1), and sudden death (1). Forty-one patients had long-term clinical and echocardiographic evaluation.(ABSTRACT TRUNCATED AT 250 WORDS)

[Preservation of the aortic valve in acute dissection of the ascending aorta]. / Préservation de la valve aortique dans les dissections aiguës de l'aorte ascendante.

The aim of this study was to evaluate the status of the native aortic valve in patients operated for acute dissection of the ascending. aorta (ADAA). Between November 1972 and November 1991, 93 patients were operated for ADAA. There were 76 men and 17 women (average age 54 +/- 12 years). The aortic valve was reserved in 80 cases (86%). In 13 patients (14%) aortic valve replacement was associated with replacement of the ascending aorta. The early mortality was 29% (27/93). The global actuarial survival rates at 5, 10 and 15 years were 60.2 +/- 5.2%, 49.7 +/- 6.1% and 26.9 +/- 9.9% respectively. Fifty patients (94%) in whom the native aortic valve was preserved were followed up. Nine patients (18%) died and average of 97 +/- 46 months after surgery. The causes of death were aortic rupture or extension of the dissection (N = 4), ischemic cardiac failure (N = 2), renal failure (N = 1), cerebrovascular accident (N = 1) and sudden death (N = 1). Forty one patients underwent transthoracic echocardiography. Seven patients developed severe aortic regurgitation, 6 of whom had to be reoperated for aortic valve replacement. Echocardiography showed absence of of minimal aortic regurgitation in 22 cases and mild aortic regurgitation with normal left ventricular function in 12 cases (in 2 cases, aortic valve replacement was associated with surgical treatment of another valvular lesion or of coronary artery disease). Therefore, aortic valve replacement was performed in 8 patients 61.5 +/- 51.2 months after the initial operation.(ABSTRACT TRUNCATED AT 250 WORDS)

Beta-adrenergic contractile reserve as a predictor of clinical outcome in patients with idiopathic dilated cardiomyopathy.

To examine the ability of beta-adrenergic contractile reserve assessment to predict the outcome of patients with heart failure, a prospective study was undertaken in 35 patients with idiopathic dilated cardiomyopathy and radionuclide ejection fraction below 40%. During right- and left-sided catheterization, right atrial and left ventricular (LV) pressures, peak positive LV dp/dt, cardiac index, and plasma norepinephrine and epinephrine concentrations were measured at baseline. After a left main intracoronary infusion of dobutamine (25 to 200 micrograms.min-1), beta-adrenergic contractile responsiveness was assessed as the net increase in peak positive LV dp/dt (delta LV dp/dt). After the initial examination, patients were treated with diuretics, digitalis, and angiotensin converting enzyme inhibitors and then followed-up. After a mean follow-up period of 13 +/- 7 months, two groups of patients were distinguished: those who responded to medical therapy (group A, n = 26) and those with clinical deterioration (group B, n = 9) leading to death (n = 4) or heart transplantation (n = 5). Initial peak positive LV dp/dt, LV end-diastolic pressure, cardiac index, and LV ejection fraction were better in group A than in group B (p less than 0.001). Initial plasma norepinephrine and epinephrine concentrations were significantly higher and delta LV dp/dt was lower in group B than in group A (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Left ventricular flow propagation during early filling is related to wall relaxation: a color M-mode Doppler analysis.

OBJECTIVES: This study was designed to evaluate the relation between the velocity of flow propagation and left ventricular relaxation by using color M-mode Doppler echocardiography to analyze flow propagation in the left ventricle. BACKGROUND: Noninvasive attempts to identify alterations in left ventricular relaxation have been hampered because both the relaxation rate and left atrial filling pressure are the determinants of peak early velocity and filling rate. METHODS: Color M-mode velocity data were transferred to a microcomputer and compared with conventional pulsed Doppler data to assess the ability of color M-mode echocardiography to analyze velocity field properties. The velocity of flow propagation was measured as the slope of the flow wave front during early filling in normal subjects (n = 29) and in patients with disease that alters relaxation (dilated cardiomyopathy [n = 31], ischemic cardiomyopathy [n = 8], hypertrophic cardiomyopathy [n = 5], systemic hypertension [n = 22] and aortic valve disease [n = 25]). In nine patients with end-stage dilated cardiomyopathy, echocardiographic and left heart catheterization data were obtained at baseline and during intracoronary dobutamine infusion. RESULTS: Color M-mode and pulsed Doppler echocardiographic data were highly correlated (n = 217, r = 0.94, p less than 0.0001, velocity range 0.2 to 1.5 m/s). The velocity of flow propagation was lower in patients than in normal subjects (0.46 +/- 0.15 vs. 0.84 +/- 0.11 m/s, p less than 0.0001). The decrease was significant in all disease forms with or without left ventricular dilation. The velocity of flow propagation was related to peak early velocity in normal subjects (p less than 0.001) but not in patients. It varied inversely with the isovolumetric relaxation time constant during dobutamine infusion and the two variables were highly correlated (p less than 0.0001). CONCLUSIONS: The velocity of flow propagation during early filling seems to be highly dependent on the left ventricular relaxation rate and could be an important tool in studying diastolic function.