Transesophageal Stress Echocardiography Research Articles

Use of Intraoperative Dobutamine Stress Echocardiography on Outcomes of Septal Myectomy

Septal myectomy is the standard treatment for obstructive hypertrophic cardiomyopathy. We studied the impact of intraoperative pre- and postprocedure dobutamine stress transesophageal echocardiography on surgical planning and outcomes of septal myectomy. We identified 55 patients undergoing septal myectomy over a 24-month period. All patients underwent resting and dobutamine stress (20-40 mcg/kg/min) echocardiography after induction of anesthesia pre- and postprocedure. Demographic, clinical, and imaging data were prospectively collected. Mean age was 59 (42-68). A total of 69% of patients were New York Heart Association Class III/IV. During outpatient evaluation, peak preoperative resting left ventricular outflow tract gradient was 91.6 mm Hg and 94% (50/53) had severe stress-induced mitral regurgitation (MR). After induction, peak resting gradient fell to 47.8 mm Hg and 43% (24/55) had improved gradients (<30 mm Hg). With stress, preprocedure left ventricular outflow gradient increased to 130 mm Hg and all occult gradients were unmasked. Postprocedure, peak resting and stress gradients were substantially reduced (10.2 ± 6.8 mm Hg and 23.6 ± 8.5 mm Hg, respectively). With stress, 84% (42/50) demonstrated reduction in severity of MR to none and/or mild with no patients having greater than moderate. Postprocedure stress echocardiography identified 3 patients with residual gradients, which led to return to bypass for additional procedures and resulted in resolution of elevated residual gradients. Postoperative 60-day stress echocardiography showed sustained resolution of gradients and MR. In this series, 43% of patients had occult left ventricular outflow gradients after induction of anesthesia. Intraoperative stress echocardiography during septal myectomy is useful to unmask occult gradients and confirm adequate myectomy. This imaging strategy is associated with reliable relief of obstruction and MR as demonstrated at 60-day follow-up.

Diagnosis and treatment of aortic valve stenosis

Aortic valve stenosis (AS) is the most frequently observed valvular heart disease. Once it is symptomatic the mortality rapidly increases. The diagnostic gold standard is transthoracic echocardiography. By measuring the maximum transvalvular velocity, mean transaortic pressure gradient and aortic valve opening area, classification of the type of stenosis can be defined. A differentiation is made between high-gradient AS, low-flow low gradient AS with reduced ventricular ejection fraction (<50%) and the paradoxical low-flow low-gradient AS with preserved ventricular function (≥50%). In some cases, additional diagnostic tools are necessary using dobutamine stress echocardiography, transesophageal echocardiography and cardiac computed tomography. The treatment follows an individualized approach. In cases of indications for valve replacement the multidisciplinary heart team takes into account the patient's age and individual risk for deciding whether an open surgical approach or transcatheter aortic valve implantation is indicated.

Stress-echocardiography is underused in clinical practice: a nationwide survey in Austria

The wide area of application, including coronary artery disease, valvular heart disease, or pulmonary hypertension makes stress echocardiography (SE) a powerful, cost-effective imaging modality in cardiology. The role of this technique in clinical practice in Austria is unknown. A nationwide survey included all departments for cardiology and/or internal medicine in the years 2008 and 2013. By electronic questionnaire demographics, indication for the test, the numbers of examined cases per year, operators, and various applied techniques of SE were interrogated and completed by telephone interviews. Data could be obtained from all 117 departments. In the year 2007 in 58 (50%) and in 2012 57 (49%) departments SE was available in Austrian hospitals. More than 100 SEs per year were performed by only four (7%) units in the year 2007 and by five (8%) in 2012. Physical exercise, dobutamine, and dipyridamole SE were available in 27 (46%), 52 (90%), and six (10%) units in 2007, and in 15 (27%), 52 (91%), and five (9%) units in 2012, respectively. In 2007 41 (71%) and in 2012 26 (46%) echo-labs administered contrast agents during SE. Transesophageal SE and 3D-echo was performed in one (2%) and three (5%) units in 2007, and in six (10%) and four (7%) echo-labs in 2012. This representative survey demonstrates the underuse of SE in clinical practice in Austria. Even in established application fields performance is low, examination frequencies as recommended by the cardiology societies are fulfilled only by a minority of institutions.

Does increased aortic stiffness predict reduced coronary flow velocity reserve in patients with suspected coronary artery disease?

In recent studies, reduction in coronary flow velocity reserve (CFR) has been demonstrated in patients with increased aortic stiffness. Stress transoesophageal echocardiography (TEE) is a suitable method for the simultaneous evaluation of CFR and aortic stiffness parameters. The present study was designed to test whether increased echocardiography-derived aortic elastic modulus [E(p)] predicts impaired CFR in patients with suspected coronary artery disease (CAD). The present study comprised 158 patients with suspected CAD. A CFR value < 2 was considered abnormal. Both men grade of aortic atherosclerosis (AA) (as a morphologic characteristic) (1.31 ± 0.68 vs. 1.02 ± 0.89, p < 0.05) and aortic distensibility (E(p) as a functional characteristic) (892 ± 594 mmHg vs. 723 ± 495 mmHg, P < 0.05) were increased in subjects with CFR < 2. In ROC analysis, the cut-off value for E(p) to predict impaired CFR was ≥ 670 mmHg, with 61% sensitivity and 61% specificity (ROC area 0.60, p = 0.026). The logistic regression model identified higher AA grade (hazard ratio (HR) 2.01, p < 0.05) and increased E(p) as independent predictors of reduced CFR (HE 1.10, p < 0.05). Increased aortic stiffness predicts impaired CFR in patients with suspected CAD.

Usefulness of an accelerated transoesophageal stress echocardiography in the preoperative evaluation of high risk severely obese subjects awaiting bariatric surgery

BackgroundSevere obesity is associated with an increased risk of coronary artery disease (CAD). Bariatric surgery is an effective procedure for long term weight management as well as reduction of comorbidities. Preoperative evaluation of cardiac operative risk may often be necessary but unfortunately standard imaging techniques are often suboptimal in these subjects. The purpose of this study was to demonstrate the feasibility, safety and utility of transesophageal dobutamine stress echocardiography (TE-DSE) using an adapted accelerated dobutamine infusion protocol in severely obese subjects with comorbidities being evaluated for bariatric surgery for assessing the presence of myocardial ischemia.MethodsSubjects with severe obesity [body mass index (BMI) >40 kg/m2] with known or suspected CAD and being evaluated for bariatric surgery were recruited.ResultsTwenty subjects (9M/11F), aged 50 ± 8 years (mean ± SD), weighing 141 ± 21 kg and with a BMI of 50 ± 5 kg/m2 were enrolled in the study and underwent a TE-DSE. The accelerated dobutamine infusion protocol used was well tolerated. Eighteen (90%) subjects reached their target heart rate with a mean intubation time of 13 ± 4 minutes. Mean dobutamine dose was 31.5 ± 9.9 ug/kg/min while mean atropine dose was 0.5 ± 0.3 mg. TE-DSE was well tolerated by all subjects without complications including no significant arrhythmia, hypotension or reduction in blood arterial saturation. Two subjects had abnormal TE-DSE suggestive of myocardial ischemia. All patients underwent bariatric surgery with no documented cardiovascular complications.ConclusionsTE-DSE using an accelerated infusion protocol is a safe and well tolerated imaging technique for the evaluation of suspected myocardial ischemia and cardiac operative risk in severely obese patients awaiting bariatric surgery. Moreover, the absence of myocardial ischemia on TE-DSE correlates well with a low operative risk of cardiac event.

Long‐Term Prognostic Significance of Coronary Flow Velocity Reserve in Patients with Significant Coronary Artery Disease Not Involving the Left Anterior Descending Coronary Artery (Results from the SZEGED Study)

Coronary flow velocity reserve (CFR) by pulsed Doppler echocardiography is a useful hemodynamic index to evaluate the coronary microcirculatory dysfunction in the left anterior descending coronary artery (LAD). The present study was designed to evaluate the long-term predictive value of CFR for mortality in patients with right (RC) and/or left circumflex coronary artery (CX) stenosis without epicardial LAD disease. A total of 49 patients with significant RC and/or CX stenosis were enrolled in this prospective follow-up study. All patients had undergone coronary angiography demonstrating significant RC and/or CX stenosis without LAD disease and dipyridamole stress transoesophageal echocardiography as CFR measurement. The success rate of follow-up was 43 out of 49 (88%). During a mean follow-up of 97 +/- 29 months, 14 patients suffered cardiovascular deaths (12 sudden cardiac deaths and 2 strokes), and 1 patient died of pulmonal tumor. Patients who died during the follow-up had significantly lower CFR values (1.85 +/- 0.43 vs. 2.31 +/- 0.57, P < 0.05). Using ROC analysis, CFR <2.09 had the highest accuracy in predicting cardiovascular survival (sensitivity 80%, specificity 57%, area under the curve 73%, P = 0.003). The logistic regression model identified only CFR as an independent predictor of survival (hazard ratio [HR] 6.26, 95% CI of HR 1.23-19.61, P = 0.024). Long-term prognostic significance of CFR for the prediction of mortality has been demonstrated during a 9-year follow-up in patients with significant coronary artery disease not involving the LAD.

Long-term prognostic value of coronary flow reserve in patients without significant left anterior descending coronary artery stenosis: results from the SZEGED Study

Coronary flow reserve (CFR) measured by pulsed Doppler echocardiography is a useful hemodynamic index to evaluate coronary microcirculatory (dys)function in the left anterior descending coronary artery (LAD), in the absence of macrovascular lesions. The present study was designed to evaluate long-term prognostic value of CFR in patients without significant epicardial LAD stenosis. A total of 166 patients without significant LAD stenosis were enrolled in this prospective follow-up study. Coronary angiography demonstrated absence of significant LAD disease in all cases. All patients underwent transthoracic and stress transesophageal echocardiography (CFR measurement) and coronary angiography. The success rate of follow-up was 124 out of 166 (75%). During a mean follow-up of 93+/-34 months 27 patients died, including 16 sudden cardiac deaths, 3 acute heart failures, 2 strokes, while 6 patients had pulmonary or gastrointestinal malignancies. Using ROC analysis, the best cut-off value for CFR was 2.13 to predict survival (sensitivity 67%, specificity 60%, area, under the curve 62%, p = 0.046). Patients with CFR < 2.13 had significantly more events (32% vs. 13%, p<0.05). The logistic regression model identified CFR (hazard ratio (HR) 2.43, p = 0.04) and left ventricular end-systolic volume (HR 1.09, p = 0.03) as independent predictors of survival. Long-term prognostic significance of CFR for prediction of survival has been demonstrated during a long-term follow-up in patients without significant LAD stenosis.

Prediction of myocardial viability, after coronary revascularization by intraoperative dobutamine stress transesophageal echocardiography

Objective To predict myocardial viability and recovery of regional ventricular function using intraoperative dobutamine stress transesophageal echocardingrapby (DSE) in patients with chronic iachemic left ventricular dysfunction. Methods With institutional review board approval and informed consent 24 NYHA class Ⅱ or Ⅲ patients (19 males, 5 females) aged 50-75 yr, weighing 55-90 kg undergoing elective coronary artery bypass graft (CABG) were studied. Transesophageal echocardiography was used during operation. Regional wall motion (RWM) was semi-quantitatively estimated and scored by 16 segment images as suggested by American Society of Echocardiograpby Committee after tracheal intubation (T_1), during dobutamine infusion (T_2) and after revascularization (T_3) (0=wall motion is augmented, 1 = normal motion, 2,3 = slightly, severely weakened motion, 4 = no motion, 5 = reverse motion). Viabihty was defined as improvement in the motion of regional wall (> 0.5 cm thick) by ≥ 1 score. The accuracy, specificity, sensitivity and positive/negative prediction value (PPV, NPV) of DSE for predicting the myocardial viability after revascularization were assessed. Results The ejection fraction was (39±11) % after tracheal intubation and reached (47±8) % at 3 min of dobutamine infusion and (47±9) % after coronary revascularizatien. The predicted improvement in regional myocardial function by DSE was 36.3% and significantly lower than the segmental recovery of myocardial function after revascularization (43.2%). The sensitivity, specificity, accuracy, PPV and NPV of DSE in predicting myocardial viabihty were 75.3%, 92.7%, 85.3%, 88.4% and 83.5% respectively. Conclusion Intraoperative DSE is effective in assessing the recovery of regional myocardial function after CABG. Key words: Dobutamine; Echocardiography; stress; Myocardium; Tissue survival; Coronary artery bypass

Long‐term prognostic role of coronary flow velocity reserve in patients with aortic valve stenosis – insights from the SZEGED Study

Coronary flow velocity reserve (CFR) is markedly reduced in severe aortic valve stenosis (AS). Independent prognostic value of pulsed-wave Doppler echocardiography-derived CFR was seen in a variety of diseases. However, the prognostic significance of CFR by pulsed-wave Doppler echocardiography has never been evaluated in patients with AS. A total of 49 AS patients (mean age: 63 +/- 9 years, 26 men) were enrolled in this prospective follow-up study; they all had undergone standard transthoracic Doppler-echo study, coronary angiography and dipyridamole stress transoesophageal echocardiography as CFR measurement. During a mean follow-up of 82 +/- 38 months, 18 patients suffered cardiovascular death and one patient had non-fatal stroke. Other two patients underwent reoperation of dysfunctional prosthetic aortic valve. Using receiver operator curve (ROC) analysis, CFR <2.13 had the highest accuracy in predicting cardiovascular outcome (sensitivity 90%, specificity 46%, area under the curve 66%, P = 0.02). By univariable analysis, diabetes mellitus, hypertension, presence of coronary artery disease and lower CFR were significant predictors of cardiovascular morbidity and mortality. Multivariable regression analysis showed that only lower CFR [hazard ratio (HR) 1.67, 95% CI of HR: 1.05-4.29, P < 0.05] was independent predictor of cardiovascular outcome. Long-term prognostic significance of CFR for prediction of cardiovascular morbidity and mortality has been demonstrated during a 9-year follow-up in patients with AS. Despite a relatively small number of patients were followed, CFR was found to be an independent predictor for future cardiovascular events in AS patients.

Coronary Flow Velocity Reserve and Aortic Distensibility Indices in Hypertensive Patients with Hypercholesterolaemia and Normal Epicardial Coronary Arteries

The aim of the present study was to assess the relationship between coronary flow velocity reserve (CFR), aortic distensibility indices, and levels of plasma total cholesterol (TC) in arterial hypertension. We studied 39 consecutive hypertensive patients free of coronary artery disease. Eighteen of them had normal TC and 21 had 18 high TC. Coronary flow velocity reserve and aortic elastic moduli were measured during stress transoesophageal echocardiography. Reduced CFR (2.41 ± 0.75 vs. 1.97 ± 0.60, p < 0.05), increased aortic elastic modulus (in 103 mmHg) (0.56 ± 0.41 vs. 0.77 ± 0.29, p < 0.05) and Young's modulus (in 103 mmHg) (5.42 ± 4.03 vs. 8.57 ± 4.79, p < 0.05) were found in hypercholesterolaemia.

Corroborative echocardiographic procedures: The multidisciplinary approach

Ultrasound evaluation of the hear t is primarily assessed using transthoracic echocardiography. There are limitations to this standard assessment and other advanced ultrasound techniques and tools are available. This article provides a basic introduction to three corroborative procedures (transoesophageal echocardiography, stress echocardiography and contrast echocardiography) which contribute to the overall ultrasound assessment of cardiac structure and function. Unlike standard transthoracic imaging these procedures use a multi-disciplinary team and therefore this article highlights these potential roles.

Prognostic value of coronary flow reserve and aortic distensibility indices in patients with suspected coronary artery disease

In recent studies it has been demonstrated that a reduced coronary flow reserve (CFR) is independently associated with a less benign long-term outcome. Aortic stiffness is one of the most important cardiovascular risk factors predicting cardiovascular morbidity and mortality. Vasodilator stress transesophageal echocardiography (TEE) is a suitable method to evaluate simultaneously CFR and elastic properties of the descending thoracic aorta. The aim of the present study was to assess the relative prognostic value of simultaneously measured CFR and aortic elastic properties by pulsed-wave Doppler TEE in patients with suspected or known coronary artery disease (CAD). The study comprised 157 in-hospital patients with chest pain. In all patients, stress TEE was used for the simultaneous evaluation of CFR and aortic distensibility indices [elastic modulus E(p) and Young's circumferential static elastic modulus E(s)]. During a mean follow-up of 48 +/- 8 months, 13 patients suffered cardiovascular death. By univariate analysis older age, diabetes mellitus, increased left ventricular (LV) end-diastolic diameter, increased LV mass index, lower LV ejection fraction, and lower CFR were significant predictors of cardiovascular survival. Multivariate regression analysis showed that only CFR (hazard ratio [HR] 10.31, P = 0.04), age (HR 1.20, P = 0.001), and increased left ventricular (LV) end-diastolic diameter (HR 1.14, P = 0.02) were independent predictors of cardiovascular survival. Only in the small number of patients without CAD and abnormal CFR aortic distensibility seemed to provide complementary prognostic information over CFR. In the majority of patients aortic distensibility did not offer complementary prognostic information to CFR during vasodilator stress TEE testing.

Reduction of coronary flow reserve in patients with increased aortic stiffness

Aortic stiffness is thought to affect coronary blood flow, but little is known about its influence on coronary flow reserve (CFR). The objective of the present study was to investigate the relationship between aortic stiffness and CFR in matched patients with and without increased aortic stiffness. Stress transoesophageal echocardiography (TEE) as the CFR measurement and coronary angiography were performed in all cases. Increased aortic stiffness was defined if elastic modulus Ep > 680 mmHg. The following patient populations free of coronary artery disease were compared: 36 subjects with normal aortic distensibility and 19 age-, sex-, and risk factor-matched patients with increased aortic stiffness. CFR was significantly reduced in patients with increased aortic stiffness as compared with cases with normal aortic distensibility (2.64 +/- 1.16 vs. 2.12 +/- 0.58, p <0.01). Hyperaemic diastolic flow velocities were reduced in patients with increased aortic stiffness (129.5 +/- 36.6 cm/s vs. 102.1 +/- 39.8 cm/s, p <0.05). Negative correlations were found between Ep and hyperaemic diastolic coronary flow velocity (r = -0.41, p < 0.01) and CFR (r = -0.21, p < 0.05). CFR is reduced in patients with increased aortic stiffness and negative correlations exist between these functional parameters.

Reduced aortic distensibility and coronary flow velocity reserve in diabetes mellitus patients with a negative coronary angiogram

Structural and functional abnormalities of the aortic wall and disturbances of the coronary circulation with presumed microvascular complications have been reported in patients with diabetes mellitus. To simultaneously establish the coronary flow velocity reserve (CFVR) and aortic distensibility indexes in type 2 diabetes mellitus patients who have normal epicardial coronary arteries by stress transesophageal echocardiography (STEE). The elastic properties of the descending aorta and the CFVR were evaluated simultaneously in 18 type 2 diabetes mellitus patients who had negative coronary angiograms. These results were compared with those of 21 nondiabetic subjects with normal epicardial coronary arteries and 24 patients with left anterior descending coronary artery (LAD) stenosis. STEE was used for the evaluation of elastic moduli of the descending aorta. The CFVR was calculated as the ratio of the average peak diastolic flow velocity during hyperemia to that at rest. The CFVR of diabetic patients with normal epicardial coronary arteries and those with LAD stenosis was similarly decreased compared with the controls (2.10+/-0.63 and 1.78+/-0.47 versus 2.76+/-1.25, P<0.05 and P<0.001, respectively). The elastic modulus (in 103 mmHg) was similarly increased in patients with diabetes mellitus and normal epicardial coronary arteries, and in those with LAD stenosis, compared with the control subjects (0.94+/-0.82 and 0.91+/-0.59 versus 0.49+/-0.19, P<0.05 and P<0.05, respectively). It may be stated that reduced aortic distensibility (increased elastic modulus) and the CFVR were demonstrated simultaneously during STEE in diabetic patients compared with nondiabetic subjects with negative coronary angiograms.

Simultaneous echocardiographic evaluation of coronary flow velocity reserve and aortic distensibility indices in hypertension

The coronary flow velocity reserve (CFVR), a measure of endothelial function in coronary circulation, can be measured semi-invasively in the left anterior descending coronary artery by using stress transesophageal echocardiography (TEE). During the same stress TEE, aortic distensibility indices (elastic modulus [E(p)] and Young's circumferential static elastic modulus [E(s)]) can be assessed. The purpose of the present study was to examine whether stress TEE is valuable method for parallel evaluation of CFVR, E(p), and E(s) in patients with hypertension. A total of 38 patients with chest pain but with a negative coronary angiogram were enrolled into the present study, which included examination of the presence or absence of hypertension. Significant coronary stenosis was considered present in the event of a luminal diameter reduction of >50% on use of the "worst view method." Patients with significant coronary or valvular heart disease, atrial fibrillation, heart failure, unstable angina pectoris, acute myocardial infarction, or diabetes mellitus were excluded from the study. Stress TEE was performed in each case to evaluate CFVR, E(p), and E(s). Coronary flow velocity reserve and diastolic coronary flow velocities measured at peak stress were decreased in hypertensive patients as compared with normotensive subjects. E(p) and E(s) were significantly increased in hypertensive patients. In conclusion, it can be stated that Stress TEE is a useful tool for the simultaneous evaluation of the CFVR, E(p), and E(s) in hypertension. The CFVR and aortic distensibility are decreased in hypertension.

Hypotension During Dobutamine Stress Transesophageal Echocardiography: Relationship with Provoked Left Ventricular Obstruction

The mechanism of hypotension during dobutamine stress (DS) echocardiography is unknown. The role of left ventricular outflow tract (OT) or midcavitary (MID) obstruction provoked during stress in this process remains controversial. We hypothesized that left ventricular OT obstruction would account for hypotension as opposed to MID obstruction. Multiplane DS transesophageal echocardiography (TEE) was performed in 142 adult patients who displayed no resting obstruction or DS-provoked ischemia. TEE was used to identify the precise site of obstruction. Dobutamine was infused from 5 to 40 microg/kg/min and atropine as needed. Continuous wave Doppler was performed from appropriate views to assess for obstruction. Ventricular obstruction was provoked at the OT in 13 patients, MID in 10 patients, and at both sites in 4 patients. A total of 115 patients without dobutamine-induced obstruction served as control subjects. Systolic blood pressure at rest was similar in all groups, but decreased to a greater magnitude from rest to peak stress in the OT (-20 +/- 40 mm Hg) and MID (-29 +/- 38 mm Hg) groups as compared with the control group (8 +/- 30 mm Hg). A hypotensive response (ie, decrease in systolic blood pressure > or = 20 mm Hg from baseline to peak stress) was significantly greater in OT (69%, P = .001) and MID (60%, P < .05) groups as compared with the control group (19%). Heart rate and ejection fraction at rest or peak did not differ among groups. Among clinical and hemodynamic variables, left ventricular OT (relative risk 5.9; 95% confidence interval 1.9-18; P < .002) and MID (relative risk 3.6; 95% confidence interval 1.1-12; P < .05) obstructions were the only predictors for a hypotensive response. Hypotension during DS TEE occurs commonly when ventricular obstruction is provoked. These data support a causal relationship between a provoked ventricular obstruction and hypotension during DS TEE.

Stress transesophageal echocardiography to simultaneously detect coronary and aortic vascular dysfunction in hypercholesterolemia: image two birds with one stone?

Stress transesophageal echocardiography to simultaneously detect coronary and aortic vascular dysfunction in hypercholesterolemia: image two birds with one stone?

Impaired coronary flow velocity reserve and aortic distensibility in patients with untreated hypercholesterolemia—an echocardiographic study

Hypercholesterolemia is a primary risk factor for the development of atherosclerosis and leading to severe stages of coronary artery disease (CAD) and aortic atherosclerosis (AA). The objective of this investigation was to measure elastic modulus [(E(p), in 10(3) mmHg] and Young's circumferential static elastic modulus [(E(s), in 10(3) mmHg] as aortic distensibility indices and coronary flow velocity reserve (CFR) in untreated hypercholesterolemic (HC) patients in the course of the same stress transesophageal echocardiography (TEE) and to compare their results to normochole- sterolemic (NC) subjects. The following patient populations were compared: 17 NC subjects with negative coronary angiograms, 18 patients with untreated hypercholesterolemia with a negative coronary angiogram and 23 HC patients with significant left anterior descending coronary artery (LAD) disease. All patients underwent coronary angiography, transthoracic and stress TEE examinations. CFR was significantly reduced in patients of both groups with hypercholesterolemia as compared to NC subjects (1.99+/-0.76 and 1.79+/-0.32 vs. 2.58+/-0.63, P<0.05, respectively). E(p) was significantly increased in HC patients with negative coronary angiograms as compared to NC subjects (0.39+/-0.18 vs. 0.67+/-0.19, P<0.05), while further increase was found in HC patients with LAD disease (0.67+/-0.19 vs. 1.09+/-0.52, P<0.05). E(s) behaved similarly (4.06+/-2.73 vs. 7.60+/-3.70 vs. 11.38+/-6.91, P<0.05, respectively). In conclusion it may be stated that CFR and aortic distensibility indices can be evaluated simultaneously by stress TEE in HC patients. CFR and aortic distensibility were impaired in HC patients as compared to NC subjects.

Is the coronary flow velocity reserve improvement after aortic valve replacement for aortic stenosis transient? Results of a 3-year follow-up

The coronary flow velocity reserve (CFR) is decreased in patients with aortic valve stenosis (AS). The aim of the present prospective study was to examine the CFR in AS patients with normal epicardial coronary arteries during a 3-year follow-up of aortic valve replacement (AVR). A total of 30 AS patients (17 women and 13 men) were enrolled in this prospective follow-up study; they all had a normal coronary angiogram and underwent dipyridamole stress transesophageal echocardiography (STEE) for CFR measurement before AVR. Nine of them participated in this 3-year follow-up study, and all patients were examined 16 months and 3 years after AVR by STEE. The CFR of AS patients was decreased before AVR. Different extents of diastolic coronary flow velocity reduction (resting and posthyperaemic) were observed resulting in a significant CFR improvement, despite the low number of patients during the 16-month follow-up. A further posthyperaemic flow velocity reduction was demonstrated after the 3-year follow-up, resulting in a significant CFR impairment. The CFR decreased in 5 cases, but remained practically unchanged in 3 after the first CFR measurement; only the CFR of 1 patient improved minimally. The main finding of the current study is that the CFR improvement 16 months after AVR, which paralleled the regression of the left ventricular hypertrophy, was found to be transient. Coronary flow velocity reserve impairment was demonstrated after the long-term (3-year) follow-up in most of the patients, which could not be explained by extravascular compressive forces.

Non-fluoroscopic mapping systems for electrophysiology: the ‘tool or toy’ dilemma after 10 yearsThe opinions expressed in this article are not necessarily those of the Editors of the European Heart Journal or of the European Society of Cardiology.

Searching in PubMed for the string ‘tool or toy’ in the title of medical papers, we found that over the past three decades about 50 papers brought up the dilemma concerning whether a novel technology is a useful tool, or merely an expensive toy. The papers are from 15 different medical disciplines spanning from radiology, neurology, anaesthesia, and surgery. Surprisingly, in almost half of these papers the ‘tool or toy’ dilemma is posed for new technologies introduced in the cardiovascular field. Several of them, such as stress echocardiography and transoesophageal echocardiography, have become widely diffused and have definitely become routine practice. Although this analysis of the medical literature is gross, the result underlines that this dilemma is not so rare. In fact, new technologies are periodically proposed and the reaction of the medical community is usually quite ambiguous, varying from the hardest scepticism to the warmest enthusiasm. Actually, far from being an expression of physicians' uncertainty, the dilemma is justified by the fact that on one hand new technologies, especially in their early phases, are associated with high costs for equipment acquisition and their disposable parts, that the field of application is not well defined, and that the initial version is usually not completely developed because the engineer's work requires physician's feedback to ameliorate and render user friendly, brand new technologies. On the other hand, the introduction of new technologies may be the first step in a revolution which advances the frontiers of medical science and therapeutic approaches by providing more effective treatments in an always increasing cohort of patients. In 1996, the in vivo use of a non-fluoroscopic magnetic technology for endocardial navigation and mapping of the heart was reported.1 Although initially the focus was on the fact that the position of the catheter could be … *Corresponding author. Tel: +39 0332 278934; fax: +39 0332 393309. E-mail address : rdeponti{at}alice.it