Advantages of real time three-dimensional echocardiography in the assessment of right ventricular volumes and function in patients with pulmonary hypertension compared with conventional two-dimensional echocardiography.

BACKGROUND: In recent years, right ventricular (RV) function has acquired greater relevance as a clinical and prognostic marker in many physiopathological conditions. The study aims to point out the value of real time three-dimensional echocardiography (RT3DE) and tissue Doppler imaging (TDI) in the evaluation of patients affected by pulmonary hypertension (PH), compared with conventional two-dimensional (2D) echocardiography. METHODS: We enrolled 44 subjects affected by PH who underwent 2D and Doppler echocardiography, RT 3D Echocardiography and TDI evaluation of the RV, and a healthy control group. PH itself can induce severe functional and structural abnormalities of the RV, such as RV hypertrophy, RV dilation, and RV systolic and diastolic dysfunction. RESULTS: In this study, RV FAC, and TAPSE showed marked alterations in patients with PH compared to the control group (C): (RVFAC: [PH] 0.29 ± 0.07 vs. [C] 0.49 ± 0.05%, P < 0.0001; TAPSE: [PH] 15.3 ± 3.2 vs. [C] 21.1 ± 2.6 mm, P > 0.0001). The 3D RV end-diastolic volume was significantly higher in PH than in C (PH) (138.7 ± 25.3 vs. [C] 82.8 ± 12.5 mL, P < 0.0001] as well as 3D RV end-systolic volume (PH) (97.6 ± 21.5 vs. [C] 39.3 ± 9.5 mL, P < 0.0001). The 3D RV ejection fraction (EF) was significantly lower in the pulmonary hypertension group than in healthy subjects (31.8 ± 6.8 vs. [C] 52.5 ± 4.7%, P < 0.0001). CONCLUSIONS: In patients with PH, evaluation of the RV diastolic and systolic volume and EF by RT3DE has shown a higher discriminating power in comparison, respectively, with 2DRV diastolic area and the relative fractional area changes.

Prevalence of left ventricular hypertrophy and determinants of left ventricular mass in obese women.

BACKGROUND: Obesity is frequently associated with left ventricular hypertrophy (LVH), a condition leading to an increased cardiovascular risk. AIM: The objective of this study was to evaluate the prevalence of LVH in a cohort of obese women, with a main focus on the anthropometric and clinical parameters that are associated with an increased left ventricular mass (LVM). METHODS: The study was performed in 166 obese female patients. LVM was measured by echocardiography. The influence of various parameters on LVM was assessed by multivariate analysis. RESULTS: The prevalence of LVH was drastically different depending on the type of indexed LVM, being 19.9% when the LVM was indexed for body surface area and 72.3% when indexed for height. Age, duration of obesity, weight, waist-to-hip ratio, pulse pressure and hypertension retained an independent direct correlation with the LVM, explaining 39.6% of the overall LVM variability. Among the parameters of the metabolic syndrome, the increase in blood pressure was the main determinant of increased LVM. CONCLUSIONS: By using allometric indexation of LVM for height, the results of our study indicate a high prevalence of LVH in a cohort of obese women. Hypertension, pulse pressure, age, duration of obesity, bodyweight and fat distribution, expressed as waist-to-hip ratio, predict 40% of LVM variation.

Acute improvement in arterial-ventricular coupling after transcatheter aortic valve implantation (CoreValve) in patients with symptomatic aortic stenosis.

The recent development of transcatheter aortic valve implantation (TAVI) to treat severe aortic stenosis (AS) offers a viable option for high-risk patients categories. Our aim is to evaluate the early effects of implantation of CoreValve aortic valve prosthesis on arterial-ventricular coupling by two dimensional echocardiography. Sixty five patients with severe AS performed 2D conventional echocardiography before, immediately after TAVI, at discharge (mean age: 82.6 ± 5.9 years; female: 60%). The current third generation (18-F) CoreValve Revalving system (Medtronic, Minneapolis, MN) was used in all cases. Vascular access was obtained by percutaneous approach through the common femoral artery; the procedure was performed with the patient under local anesthesia. We calculated, apart the conventional parameters regarding left ventricular geometry and the Doppler parameters of aortic flow (valvular load), the vascular load and the global left ventricular hemodynamic load. After TAVI we showed, by echocardiography, an improvement of valvular load. In particular we observed an immediate reduction of transaortic peak pressure gradient (P < 0.0001), of mean pressure gradient (P < 0.0001) and a concomitant increase in aortic valve area (AVA) (0.97 ± 0.3 cm(2)). Left ventricular ejection fraction improved early after TAVI (before: 47 ± 11, after: 54 ± 11; P < .0001). Vascular load, expressed by systemic arterial compliance, showed a low but significant improvement after procedure (P < 0.01), while systemic vascular resistances showed a significant reduction after procedure (P < 0.001). As a global effect of the integrated changes of these hemodynamic parameters, we observed a significant improvement of global left ventricular hemodynamic load, in particular through a significant reduction of end-systolic meridional stress (before: 80 ± 34 and after: 55 ± 29, P < 0.0001). The arterial-valvular impedance showed a significant reduction (before: 7.6 ± 2 vs after: 5.8 ± 2; P < 0.0001. Furthermore we observed a significant reduction with a normalization of arterial-ventricular coupling (P < 0.005). With regard to left ventricular (LV) efficiency, we observed, after the procedure, a significant reduction of stroke work (P < 0.001) and potential energy (P < 0.001), with a significant increase of work efficiency early after the procedure (P < 0.001). Our results showed that the TAVI procedure was able to determine an early improvement of the global left ventricular hemodynamic load, allowing a better global LV performance. Further follow-up investigations are needed to evaluate these results in a more prolonged time observation.

Early left ventricular mechanics abnormalities in prehypertension: a two-dimensional strain echocardiography study.

BACKGROUND: Prehypertension predicts established hypertension. In this study, the aim was to analyze left ventricular (LV) mechanics in borderline prehypertensive (pre-HT) and hypertensive (HT) subjects through two-dimensional (2D)-strain echocardiography and then evaluate possible relations between cardiac parameters and insulin metabolism (homeostasis model assessment of insulin resistance (HOMA(IR)). METHODS: Seventy-four consecutive newly diagnosed, untreated HT were divided, on the basis of their office blood pressure (BP) measurements, confirmed by ambulatory BP monitoring (ABPM), in 41 borderline pre-HT (ABPM: 122.5 +/- 6.7/76.2 +/- 5.2 mm Hg) and 33 never-treated mild HT (ABPM: 138.3 +/- 7.3/87.6 +/- 7.1 mm Hg). Thirty-three healthy normotensive (NT) controls (ABPM: 114.8 +/- 6.3/73.1 +/- 6.1 mm Hg) (P < 0.0001) were also studied (NT). All subjects performed 2D color Doppler and pulsed-wave tissue Doppler imaging (PW-TDI). RESULTS: Left ventricular mass (LVM) was significantly higher in pre-HT (39.2 +/- 8.7 g/m(2.7)) and in HT (43.6 +/- 8.5 g/m(2.7)) compared with NT (30.9 +/- 7.4 g/m(2.7)) (P < 0.0001). A mild LV diastolic dysfunction was found both with Doppler mitral flow velocity and PW-TDI at mitral annulus level analysis. Longitudinal 2D strain in pre-HT (-18.9% +/- 3.4) and in HT (-18.0% +/- 3.3) was significantly lower than in NT (-23.9% +/- 3.0) (P < 0.002). These LV abnormalities were associated with systolic ABPM, LVM, and HOMA(IR). CONCLUSIONS: Early abnormalities of LV longitudinal systolic deformation were found both in pre-HT and HT, together with a mild LV diastolic dysfunction. In both groups this early cardiac systolic and diastolic dysfunction is associated to insulin resistance, systolic pressure load, and cardiac remodeling.

Early impairment of left ventricular function in hypercholesterolemia and its reversibility after short term treatment with rosuvastatin A preliminary echocardiographic study.

BACKGROUND: Hypercholesterolemia contributes to coronary heart disease but little is known about its direct effect on myocardial function. We evaluated left ventricular function using echocardiography and the effect of treatment with rosuvastatin in a group of patients with primary hypercholesterolemia. METHODS AND RESULTS: Thirty-three patients with primary hypercholesterolemia (HC) and without evidence of coronary heart disease and 25 aged matched healthy volunteers (C) were submitted to conventional echocardiography, pulsed wave tissue Doppler imaging (PWTDI), color Doppler myocardial imaging (CDMI) and integrated backscatter (IBS). Echocardiographic evaluation was repeated after 6 months of treatment with rosuvastatin (10mg/day) in 17 patients. Compared with C, patients with HC showed lower E/A ratio (p<0.0001) and higher Tei index mit (p<0.0001), as well as lower PW TDI E/A both at septum (p<0.0001) and at lateral level (p<0.0001) and higher modified Tei index both at septal annulus (p<0.0001) and lateral annulus (p<0.0001). Integrated backscatter parameters were significantly reduced in patients with HC (CVIsept p<0.0001 and CVI post wall p<0.05). CDMI derived indices in the two groups were not different. After 6 months of Rosuvastatin treatment a significant reduction of LDL cholesterol levels (51%, p<0.0001) was registered in HC patients together with a significant improvement of longitudinal global systolic and diastolic function (Tei index) and myocardial intrinsic contractility (CVI). CONCLUSIONS: These data suggest that in patients with hypercholesterolemia exists an early cardiomyopathy characterized by systolic and diastolic dysfunction. That could produce a substratum for an "impaired preconditioning". Rosuvastatin seems able to revert systolic abnormalities.

Effects of bariatric surgery on early myocardial alterations in adult severely obese subjects.

OBJECTIVE: Aim of this study was to investigate the effect of weight loss on structural and functional myocardial alterations in severely obese subjects treated with bariatric surgery. PATIENTS AND METHODS: Thirteen severely obese patients (2 males and 11 females) were enrolled in the study. All subjects underwent conventional 2D color Doppler echocardiography. The new ultrasonic techniques used were: (a) integrated backscatter for the analysis of myocardial reflectivity, referred to pericardial interface as expression of myocardial structure (increase in collagen content) and of cyclic variation index as expression of intrinsic myocardial contractility and (b) color Doppler myocardial imaging (CDMI) for the analysis of strain and strain rate (myocardial deformability). All subjects underwent bariatric surgery and were resubmitted to echocardiographic and biochemical examination 6-24 months after surgery. RESULTS: The main finding of the present study was a quite complete normalization of myocardial functional and structural alterations after weight loss. In particular, the cyclic variation index at septum level improved from 14.6 +/- 7.0 before to 25.7 +/- 11.2 (means +/- SD) after surgery (controls: 36.2 +/- 9.1). Mean reflectivity at septum level significantly decreased from 55.8 +/- 9.5 to 46.5 +/- 8.8 (controls: 43.0 +/- 8.0). Also, the strain at septum level significantly improved after surgery (from -11.9 +/- 3.2 to -20.4 +/- 5.3; controls: -23.4 +/- 9). CONCLUSION: This study establishes: (a) the utility of new ultrasonic techniques to detect very early structural and functional myocardial alterations in severely obese patients, and (b) the regression of these subclinical abnormalities after weight loss achieved by bariatric surgery.

Left ventricular function in normotensive young adults with well-controlled type 1 diabetes mellitus.

The aim of this study was to determine whether early myocardial structural and functional systolic and diastolic alterations in asymptomatic and uncomplicated patients with type 1 diabetes mellitus (DM) could be detected using the new highly sensitive echocardiographic techniques of integrated backscatter and color Doppler myocardial imaging. Forty asymptomatic and uncomplicated patients with type 1 DM and 40 gender- and age-matched normal controls were studied. All patients were analyzed by conventional and new echocardiographic techniques (integrated backscatter and color Doppler myocardial imaging). Patients with DM showed reduced systolic function compared with controls, evidenced by significantly lower peak strain, strain rates, and cyclic variation indexes at the septum (p <0.0001, <0.01, and <0.001, respectively) and at the posterior wall level (p <0.0001, <0.0001, and <0.001, respectively). On receiver-operating characteristic curve analysis, systolic strain and the cyclic variation index showed the highest discriminating power for separating patients with DM and control subjects. Neither structural or ultrastructural nor diastolic functional abnormalities were detected. On univariate regression analysis, a significant inverse correlation was found for DM duration with conventional (E/A ratio) and unconventional (tissue Doppler imaging E/A ratio) indexes of diastolic function, in the absence of any correlation for systolic function. In conclusion, highly sensitive ultrasonic techniques demonstrate evidence of left ventricular systolic dysfunction in the early stage of type 1 DM, in the absence of ultrastructural and left ventricular diastolic functional abnormalities.

Obesity cardiomyopathy: is it a reality? An ultrasonic tissue characterization study.

Obesity is a well-established risk factor for congestive heart failure. Evidence has been provided indicating that insulin resistance could be the mediator between obesity and congestive heart failure, but the pathogenic mechanisms leading to myocardial alterations remain unclear. The aim of this study was to investigate, by ultrasonic integrated backscatter (IBS) analysis, subclinical alterations of left ventricular (LV) structure and function in severe obesity. Sixty consecutive, severely obese people, who were otherwise healthy (15 men, 45 women; mean age +/- SD = 31.8 +/- 7 years), were enrolled. A total of 48 sex- and age-matched nonobese healthy participants were recruited as control subjects. All participants underwent conventional 2-dimensional color Doppler echocardiography, pulsed wave Doppler tissue imaging at mitral annulus level, and IBS. The homeostasis model assessment insulin resistance index was used to assess insulin resistance; the index values in the obese group were significantly higher (mean +/- SD = 4.9 +/- 1.4) than in the control group (0.92 +/- 0.5, P < .0001). Obese patients had a greater LV mass index by height (58.5 +/- 14 g/m(2.7)) than did control subjects (37 +/- 8 g/m(2.7), P < .0001) because of compensation response to volume overload caused by a greater cardiac output (P < .02). Preload reserve was increased in obese patients, as demonstrated by the significant increase in left atrial dimension (P < .0001). This volumetric increase activated the Frank-Starling mechanism, and determined a significantly higher LV ejection fraction (P < .03) in obese patients as compared with control subjects. A slightly reduced LV diastolic function was demonstrated in obese patients (transmitral early to late peak diastolic transmitral flow velocities ratio = 1.1 +/- 0.7) as compared with control subjects (1.5 +/- 0.5, P < .02). Pulsed wave Doppler tissue imaging showed an impairment of diastolic LV longitudinal function and increased LV diastolic filling pressure. The IBS values at septum level, indexed by pericardium interface, were significantly higher for septum in the obese group (57.8 +/- 8%) than in the control group (42.3 +/- 9%, P < .0001). Additional IBS alterations were observed in the obese group, with a significantly lower cyclic variation index both at septum (P < .0001) and at posterior wall (P < .001) levels. A significant association was found between insulin resistance index and both the IBS index of myocardial reflectivity at septum level (expression of increased myocardial collagen content) or LV mass. In conclusion, this study demonstrates that obese patients exhibit myocardial structural and functional alterations related to insulin resistance and to LV volume overload, which could be considered the very early stage of incipient obesity cardiomyopathy.

Early textural and functional alterations of left ventricular myocardium in mild hypothyroidism.

The aim of the present study was to evaluate cardiac function and texture in patients with subclinical hypothyroidism (sHT) both by conventional and new ultrasonic intramyocardial tissue techniques. sHT was characterized by normal serum free tetraiodotironine and free triiodotironine levels and slightly increased serum TSH level. Twenty-four patients affected by sHT and 24 sex- and age-matched healthy volunteers were studied. All subjects were submitted to conventional two-dimensional (2D)-color Doppler echocardiography, pulsed wave tissue Doppler imaging (PWTDI) for the analysis of the diastolic function, color Doppler myocardial imaging (CDMI) for the analysis of regional strain and strain-rate and integrated backscatter (IBS) for the evaluation of intrinsic contractility and tissue characterization. The results of the present study were: (a) the detection in sHT subjects of a lower cyclic variation index (CVI) indicating an altered myocardial intrinsic contractility; (b) a higher ultrasonic myocardial reflectivity indicating an altered myocardial texture; (c) the detection of lower systolic strain and strain-rate indicating an alteration of myocardial regional deformability; (d) an initial impairment of left ventricular diastolic function indicated by a decrease of peak E mitral flow velocity and an increase of peak A mitral flow velocity. All parameters studied with conventional 2D-echo in sHT patients were comparable with controls, except for a mild alteration in diastolic function. A significant correlation among systo-diastolic modifications detected by CDMI and IBS and serum TSH levels were found. The CVI at septum, the PWDTI S-peak wave and the systolic strain at septum were inversely related to the serum TSH levels. In conclusion, the new intramyocardial ultrasonic techniques confirm and extend the previous knowledge on the effect of the sHT on the heart, allowing the detection of early ultrastructural and regional functional systolic and diastolic abnormalities.

Left ventricular remodeling after primary coronary angioplasty in patients treated with abciximab or intracoronary adenosine.

BACKGROUND: Primary angioplasty is the best treatment of acute myocardial infarction but fails to achieve adequate myocardial reperfusion in 25% to 30% of patients, despite TIMI grade 3 flow. Drug treatment aimed at reducing the no-reflow phenomenon may improve myocardial salvage, thus preventing left ventricular remodeling. Our aim was to evaluate the impact of abciximab and adenosine on immediate angiographic results and on 6-month left ventricular remodeling. METHODS: Ninety consecutive patients undergoing primary angioplasty with coronary stenting were randomized in a sequential alternating fashion to standard abciximab treatment (ABCX) group, intracoronary adenosine distal to the occlusion (ADO) group, or neither (CTRL) group. All patients underwent a clinical and echocardiographic follow-up at 1 and 6 months. The primary end point was the prevalence of 6-month left ventricular remodeling. RESULTS: Baseline clinical, echocardiographic, and angiographic characteristics were similar. Mean final corrected TIMI frame count was 17 +/- 9, 16 +/- 12, and 23 +/- 11 frames in ABCX, ADO, and CTRL patients, respectively (P = .002). Angiographic no-reflow was observed in 7%, 13%, and 17% of ABCX, ADO, and CTRL patients, respectively (P > .20). At 6 months, left ventricular remodeling occurred in 7%, 30%, and 30% of ABCX, ADO, and CTRL patients, respectively (P = .045), with a percent increase in end-diastolic volume of 5% +/- 13%, 15% +/- 15%, and 12% +/- 18% (P = .04). CONCLUSIONS: During primary angioplasty, abciximab enhances myocardial reperfusion, translating into a reduced incidence of 6-month left ventricular remodeling. In contrast, adenosine administration improves angiographic results but does not prevent left ventricular remodeling.

Improvement of intrinsic myocardial contractility and cardiac fibrosis degree in acromegalic patients treated with somatostatin analogues: a prospective study.

BACKGROUND: Acromegalic patients have increased left ventricular (LV) mass (M) and impaired diastolic function. AIM: Using ultrasonic cardiac tissue characterization, we evaluated the early changes in cardiac fibrosis (IBS) and intrinsic myocardial contractility (CVI) as well as their reversibility after treatment with somatostatin analogues (SMSA) in patients with acromegaly. PATIENTS AND METHODS: Twenty-two acromegalic patients with active untreated disease (Acro(UNTR)) underwent conventional Doppler echocardiography and integrated backscattering; 25 healthy subjects (controls) and eight patients with acromegaly in remission after pituitary adenomectomy (Acro(REM)) served as controls. RESULTS: As expected, Acro(UNTR) at baseline had higher LVM than controls or Acro(REM) (P < 0.001); LVM reduced in acromegalic patients after SMSA (P < 0.005 vs. baseline) while LV ejection fraction did not change. LV diastolic function was reduced in all acromegalic patients, either at baseline or after SMSA therapy (E/A ratio, 0.96 +/- 0.3 and 1.1 +/- 0.3, respectively, P < 0.002 vs. controls, 1.6 +/- 0.3). CVI was reduced in Acro(UNTR) (14.3 +/- 5.8%, P < 0.003 vs. controls, 28.7 +/- 7.5%) and greatly improved after SMSA (22.5 +/- 4.5%, P < 0.003 vs. baseline). Cardiac fibrosis was increased in Acro(UNTR) (IBS(MSI), 53.7 +/- 5.3%P < 0.002 vs. controls) and reduced after SMSA (43.7 +/- 4.2%P < 0.002 vs. baseline) albeit not reaching values observed in controls. More importantly, five of 22 (23%) Acro(UNTR) patients had normal LVM, but increased cardiac fibrosis as revealed by back scattering. IBS values and CVI% were related with serum GH and IGF-1 (P < 0.0001) levels, and the estimated duration of disease (P < 0.005). CONCLUSIONS: The present study demonstrated that active acromegalic patients had early impairment of systolic function and increased cardiac fibrosis; increased fibrosis may precede LV hypertrophy; these changes are related to the activity of disease and might improve during treatment with SMSA.

Myocardial function in severe aortic stenosis before and after aortic valve replacement: a Doppler tissue imaging study.

BACKGROUND: The aim of the study was to assess the value of Pulsed-wave Doppler tissue imaging (DTI) in assessing diastolic and systolic function in patients with severe aortic value stenosis. METHODS: Thirty-five patients with aortic stenosis (AS) (valve orifice < or = 1 cm 2 , mean age 71.8 +/- 6.2) and 35 comparable healthy subjects were studied. All subjects performed conventional 2-dimensional Doppler echocardiography and DTI at mitral annulus level. Patients with AS were divided into 2 groups: 16 patients who presented initial signs of HF and a depressed left ventricular systolic function (AS I) (EF: 35%-50%) and 19 patients were asymptomatic and had normal left ventricular systolic function (EF > 50%) (ASII). The 16 symptomatic AS patients underwent surgical aortic valve replacement and were examined after 1 year. RESULTS: DTI was able to detect abnormalities of systolic and diastolic function in AS: the significantly lower peak S velocity in AS I than in AS II and in controls, both at septum and lateral wall level; the significantly lower peak E velocity in AS I than in AS II and in controls both at septum and lateral wall level; the significantly higher peak A velocity in AS I than in AS II and in controls both at septum and lateral wall level; the significant lower E/A ratio in AS I than in AS II and in controls both at septum and lateral wall level. CONCLUSION: We found a significant inverse correlation between DTI lateral S velocity, DTI peak E velocity, lateral DTI E/A ratio, and AS peak and mean gradient. According to the results of this study we can affirm that DTI parameters surely had an important physiopathological impact in the knowledge of myocardial function in patients with severe aortic stenosis.

Left ventricular hypertrophy and its regression in essential arterial hypertension. A tissue Doppler imaging study.

The mitral annulus velocities of Doppler transmitral flow and pulsed-wave tissue Doppler imaging (TDI) were sampled by echocardiography for the assessment of left ventricular (LV) diastolic function in 118 never-treated essential hypertensive patients with normal systolic function and compared with those of 59 normotensive healthy subjects matched for age and sex. A selected group (n = 26) of the hypertensive study population was observed after 1 year of pharmacologic antihypertensive treatment to determine the behavior of TDI parameters in relation to eventual regression of LV hypertrophy (LVH). We found that the TDI early myocardial diastolic wave (E(m)) was significantly lower both in concentric and eccentric LVH. In addition, TDI late myocardial diastolic wave (A(m)) was significantly higher in concentric remodeling and concentric and eccentric hypertrophy. The TDI E(m)/A(m) ratio was significantly lower in all geometric remodeling subgroups. The E/A ratio Doppler transmitral flow velocity measured showed that of the 118 patients, only 32 (25%) could really be discriminated from normal, whereas individual analysis for TDI E(m)/A(m) at the mitral annulus septal level showed that of 118 patients 108 (91%) could be discriminated from normal P < .001). The LV mass was significantly less after 1 year of treatment (LVH regression), and TDI parameters showed a trend toward normalization, in particular of TDI E(m)/A(m) at the annular septal level. Pulsed-wave TDI analysis could enable not only the early assessment of whether a patient is still in an adaptive or compensatory phase before transition to irreversible damage (pathologic phase) but also the detection of precocious LV global diastolic dysfunction. With regard to this, more extensive randomized studies are needed to evaluate the effect of different pharmacologic treatments (calcium antagonists, beta-blockers, angiotensin I and II inhibitors) on TDI parameters.

Early impairment of myocardial blood flow reserve in men with essential hypertension: a quantitative myocardial contrast echocardiography study.

OBJECTIVE: Aims of this study were to: (1) demonstrate whether quantitative myocardial contrast echocardiography could detect an index of myocardial blood flow reserve through the analysis of refilling curves generated by microbubble transit into myocardium both at rest and after vasodilatation induced by dipyridamole; and (2) explore with this method myocardial microcirculatory function in two different models (ie, patients with essential hypertension and control subjects). METHODS: Two groups of strictly age-matched men were studied (case-control study): 12 patients who were adults (28.2 +/- 0.2 years) and asymptomatic with never-treated essential hypertension, a mild degree of left ventricular hypertrophy, and normal left ventricular function; and 12 control subjects. Quantitative myocardial contrast echocardiography was performed in all study participants. We used second-generation ultrasound microbubbles as echocardiography contrast agent. Real-time color-coded power modulation was performed with a phased-array system interfaced to a S3 transducer (1.3-3.6 MHz). RESULTS: In control subjects there was little increase in myocardial blood volume (30%) between basal and hyperemic status (P <.05); in patients with hypertension this parameter increased by 22% (P <.05). Myocardial blood velocity increased after dipyridamole by 270% in control subjects (P <.01), whereas for patients with hypertension this parameter increased only by 150% (P <.02). The index of myocardial blood flow reserve was significantly lower for patients with hypertension than in control subjects (3.3 +/- 0.3 vs 4.4 +/- 0.3, respectively; P <.01). CONCLUSION: Results of our study documented that myocardial microcirculation in young adult patients with hypertension showed an early impairment in the vasodilatation capacity of the resistance arterioles under dipyridamole-induced hyperemia, as demonstrated by a reduction of myocardial blood flow reserve. Myocardial blood velocity increased after dipyridamole induction in control subjects, whereas patients with hypertension showed a significantly lesser increase. Myocardial blood flow reserve was significantly lower for patients with hypertension because of an early impairment in vasodilatation capacity of resistance arterioles under dipyridamole-induced hyperemia.

Severe aortic stenosis and myocardial function: diagnostic and prognostic usefulness of ultrasonic integrated backscatter analysis.

BACKGROUND: The aim of this study was to assess the myocardial reflectivity pattern in severe aortic valve stenosis through the use of integrated backscatter (IBS) analysis. Patients with aortic stenosis (AS) were carefully selected in the Department of Cardiology. METHODS AND RESULTS: Thirty-five subjects (AS: valve orifice < or =1 cm2; 12 female; mean age, 71.8+/-6.2 years) and 25 healthy subjects were studied. All subjects of the study had conventional 2D-Doppler echocardiography and IBS. Backscatter signal was sampled at the septum and posterior wall levels. Patients with AS were divided into 2 groups: 16 patients with initial signs of congestive heart failure and a depressed left ventricular systolic function (DSF) (ejection fraction [EF] range, 35% to 50%) and 19 asymptomatic patients with normal left ventricular systolic function (NSF) (EF >50%). Myocardial echo intensity (pericardium related) was significantly higher at the septum and posterior wall levels in DSF than in NSF and in control subjects. IBS variation, as an expression of variation of the signal, appeared to be significantly lower in AS with DSF than in NSF and in control subjects, at both the septum and posterior wall levels. Patients with DSF underwent aortic valve replacement, and, during surgical intervention, a septal myocardial biopsy was made for evaluation of myocardium/fibrosis ratio. Abnormally increased echo intensity was detected in left ventricular pressure overload by severe aortic stenosis and correlated with increase of myocardial collagen content (operating biopsy). CONCLUSIONS: One year after aortic valve replacement, we observed a significant reduction of left ventricular mass, and, only if pericardial indexed IBS value (reduction of interstitial fibrosis) decreased, it was possible to observe an improvement of EF and of IBS variation.

Role of platelet glycoprotein IIb/IIIa inhibitors in rescue percutaneous coronary interventions.

In the setting of acute myocardial infarction, thrombolytic therapy fails to restore an adequate epicardial flow in a large number of patients. Although an increasing number of patients undergoes a percutaneous coronary intervention (PCI) after failed thrombolysis, this treatment has been poorly investigated. This review focuses particularly on the safety and prognostic impact of glycoprotein (GP) IIb/IIIa receptor inhibitors after failed thrombolysis. GPIIb/IIIa inhibitors have been demonstrated to improve the clinical outcome in patients undergoing primary PCI. However, the increased risk of bleeding with the administration of potent antiplatelet drugs after full-dose thrombolytics has limited the widespread use of GPIIb/IIIa inhibitors during rescue PCI. We recently reported that abciximab treatment during rescue PCI has a beneficial effect on the short-term prognosis, without excess bleeding complications. This result can be achieved by using the radial approach, a low-dose weight-adjusted heparin regimen, and by limiting the use of aortic counterpulsation. In conclusion, in case of thrombolysis failure, patients should be referred to tertiary hospitals where rescue PCI can be performed with expertise.

Prognostic value of myocardial viability recognized by low-dose dobutamine echocardiography in chronic ischemic left ventricular dysfunction.

This study assesses the prognostic value of myocardial viability recognized as a contractile response to inotropic stimulation in patients with left ventricular (LV) dysfunction in a large-scale prospective, multicenter, observational study. Four hundred twenty-five patients (mean age 61 +/- 10 years) with angiographically proven coronary artery disease, previous (>3 months) myocardial infarction, and severe LV dysfunction (ejection fraction <35%; mean 28 +/- 6%) were enrolled in the study. Each patient underwent low-dose dobutamine echocardiography (up to 10 microg/kg/min). Myocardial viability was identified as a rest-stress variation (Delta) in the wall motion score index (WMSI), in which each segment was scored from 1 = normal to 4 = dyskinetic in a 16-segment model of the left ventricle. Myocardial viability was identified as an improvement of >/=0.40 in WMSI. All patients were followed for a median of 3.1 years. One hundred eighty-eight were revascularized either by coronary artery bypass grafting (n = 118) or coronary angioplasty (n = 70). The only end point analyzed was cardiac death. In the revascularized group, cardiac death occurred in 4 of the 52 patients with and in 37 of the 136 patients without myocardial viability (7.7% vs 27.2%, p <0.003). Kaplan-Meier survival estimates showed a better outcome for those patients with compared to patients without myocardial viability who underwent coronary revascularization (90.1% vs 62%, p <0.0078). Thus, in severe LV ischemic dysfunction, myocardial viability by low-dose dobutamine echocardiography is associated with improved survival in revascularized patients.

Assessment of myocardial perfusion with intravenous contrast echocardiography: comparison with (99) Tc-tetrofosmin single photon emission computed tomography and dobutamine echocardiography.

The aim of the study was to evaluate the accuracy of intermittent, harmonic power Doppler (HPD) during intravenous Levovist infusion in identifying myocardial perfusion abnormalities in patients with recent infarction. Fifty-five patients with first acute myocardial infarction, successfully treated by primary PTCA, were studied after 1 month by myocardial contrast echocardiography (MCE), 99mTc tetrofosmin single photon emission computed tomography (SPECT), and low dose dobutamine echocardiography (DE). Scoring myocardial perfusion as normal, moderately, or severely reduced; MCE and SPECT were in agreement in 71% of segments(k = 0.414). Discordance was mainly due to ventricular walls with normal enhancement by MCE and moderate perfusion abnormalities by SPECT. Scoring perfusion as present or absent, the agreement significantly improved up to 86% (k = 0.59). Sensitivity and specificity of HPD for identifying SPECT perfusion defects were 63% and 93%, respectively. The agreement between MCE and SPECT was higher(85%, k = 0.627)in patients with anterior infarction. An improvement in regional contractile function was noted after dobutamine in 79 dysfunctional segments. A normal perfusion or a moderate perfusion defect by MCE were detected in 71 of 79 of these segments, while a severe perfusion defect was observed in 59 of 85 ventricular segments without dobutamine-induced wall-motion improvement. Sensitivity and specificity by HPD in detecting segments with contractile reserve were 90% and 69%, respectively. Thus, intermittent HPD during Levovist infusion allows myocardial perfusion abnormalities to be detected in patients with recent infarction. This method has a limited sensitivity but a high specificity in detecting SPECT perfusion defects, and a good sensitivity but a limited specificity in detecting contractile reserve.

Mechanical prevention of distal embolization during primary angioplasty: safety, feasibility, and impact on myocardial reperfusion.

BACKGROUND: Effective myocardial reperfusion after primary percutaneous coronary intervention (PCI) may be limited by distal embolization. We tested the safety, feasibility, and efficacy of the FilterWire-Ex (FW), a distal embolic protection device, as an adjunct to primary PCI. METHODS AND RESULTS: Fifty-three consecutive patients undergoing primary PCI with FW protection were compared with a matched control group treated by primary PCI alone. Successful FW positioning was obtained in 47 patients (89%) without complications. Histological analysis of the content of the last 13 filters showed multiple embolic debris in all cases. FW use was associated with lower postinterventional corrected TIMI frame count (22+/-14 versus 31+/-19; P=0.005) and higher occurrence of grade 3 myocardial blush (66% versus 36%; P=0.006) and early ST-segment elevation resolution (80% versus 54%; P=0.006). At multivariate analysis, FW use was the only independent predictor of early ST-segment elevation resolution and of grade 3 myocardial blush. FW patients showed lower peak creatine kinase-MB release (236+/-172 versus 333+/-219 ng/mL; P=0.013) and greater improvement at 30 days in left ventricular wall motion score index (-0.30+/-0.19 versus -0.18+/-0.26; P=0.008) and ejection fraction (+7+/-4% versus +4+/-7%; P=0.012). CONCLUSIONS: FW use during primary PCI is feasible and safe. Distal embolization prevention appears to exert a beneficial effect on markers of myocardial reperfusion and on left ventricular function improvement at 30 days.

Incremental value of ultrasonic tissue characterization (backscatter) in the evaluation of left ventricular myocardial structure and mechanics in essential arterial hypertension.

BACKGROUND: Ultrasonic backscatter parameters were analyzed in hypertensive patients and divided into groups according to both severity of left ventricular hypertrophy (LVH) (group A: no LVH [n=52]; B: mild to moderate LVH [n=55]; and C: severe LVH [n=10]) and left ventricular geometry (normal geometry [n=44]; concentric remodeling [n=8]; concentric hypertrophy [n=25]; and eccentric hypertrophy [n=40]). METHODS AND RESULTS: We studied 117 male, essential hypertensive patients and 19 normotensive, age-matched (40+/-5 years), healthy subjects who served as controls. Ambulatory and office blood pressure measurements were taken and 2-dimensional Doppler echocardiography and ultrasonic myocardial integrated backscatter (IBS) were performed. A group from the hypertensive study population (n=16) was observed after a period of pharmacological antihypertensive treatment to determine the behavior of backscatter parameters in relation to eventual regression of left ventricular mass (LVM). The cyclic variation index (CVIs) of the backscatter signal at the septum level was grouped according to each LVM level and was 29.4+/-9.3 (controls), 15+/-11 (group A), 9.5+/-10 (group B), and -1.5+/-8.6 (group C) (P<0.001). CVI septum values grouped according to left ventricular geometry were 15+/-11 (normal geometry), 12+/-7 (concentric remodeling), 7+/-11 (concentric hypertrophy), and 7.8+/-11 (eccentric hypertrophy) (P<0.01). Follow-up data demonstrate a significant reduction of LVM after therapy, as well as a significant increase in CVIs toward normal values. CONCLUSIONS: Hypertensive patients with higher LVM had the worst prognosis; in fact, those patients had the most significant CVI alterations. Regression of LVM subsequent to chronic pharmacological therapy induces a normalization of ultrasonic backscatter parameters. Ultrasonic tissue characterization (backscatter) analysis could allow early identification of patients at risk of developing complications of hypertensive cardiopathy.