Aortic valve assessment. Anatomical study of 100 healthy human hearts

PURPOSE: To assess anatomical characteristics of the aortic valve, so that they may be useful in diagnostic situations and surgical treatment. METHODS: The study analyzed 100 healthy fixed human hearts; 84% of them obtained from males, 61% of them from Caucasian individuals. The ages of the individuals ranged from 9 to 86 years (mean 30±15.5 years). The characteristics assessed related to age, sex, and race were the following: number and height of the cusps, size of the lunulae, internal and external intercommissural distance, position of the coronary ostium in relation to the aortic valve, position of the ventricular septum in relation to the aortic valve, thickness of the cusps. RESULTS: All hearts assessed had a tricuspidal aortic valve. In regard to the height of the cusps and size of the lunula, the left coronary cusp was larger, followed by the right coronary cusp and the noncoronary cusp. The internal and external intercommissural distances had mean values of 24.6±5.7mm and 19.7±7mm, respectively. In regard to the position of the coronary ostia, in one heart two ostia emerged from the left coronary sinus, and in another, the ostium was supracommissural. The mean diameter of the aorta was 21.8±3.6mm, and there were no significant sexual or racial differences, but the diameter increased progressively with the increase in age. The thickness of the cusps did not show any significant difference in the 3 points assessed. CONCLUSION: The aortic valve annulus did not show a perfect circumference, with some variations in the measurements of the annulus, in the cusps and in the relation with the ventricular septum.

In-stent restenosis. Acute and long-term outcomes after excimer laser coronary angioplasty

OBJETIVE: With the increased use of intracoronary stents, in-stent restenosis has become a clinically significant drawback in invasive cardiology. We retrospectively assessed the short- and long-term outcomes after excimer laser coronary angioplasty of in-stent restenosis. METHODS: Twenty-five patients with 33 incidents of in-stent restenosis treated with excimer laser coronary angioplasty (ELCA) were analyzed. Sixty-six percent were males, mean age of 73±11 years, and 83% were functional class III-IV (NYHA). ELCA was performed using 23 concentric and 10 eccentric catheters with a diameter of 1.6-2.2 mm, followed by balloon angioplasty (PTCA) and ultrasound monitoring. The procedure was performed in the following vessels: left anterior descending artery, 10; left circumflex artery, 8; right coronary artery, 6; left main coronary artery, 2; and venous bypass graft, 7. RESULTS: The ELCA was successful in 71% of the cases, and PTCA was 100% successful. The diameter of the treated vessels was 3.44±0.5mm; the minimal luminal diameter (MLD) increased from 0.30mm pre-ECLA to 1.97mm post-ELCA, and to 2.94mm post-PTCA (p<0.001). The percent stenosis was reduced from 91.4±9.5% before ECLA to 42.3±14.9% after ELCA and to 14.6 ± 9.3% after PTCA (p<0.001). Seventeen (68%) patients were asymptomatic at 6 months and 15 (60%) at 1 year. New restenosis rates were 8/33 (24.2%) at 6 months and 9 /33 (27.3%) at 12 months. CONCLUSION: ELCA is safe and effective for the treatment of in-stent restenosis. In the present sample, a slight increase in new restenotic lesions between 6 and 12 months was found.

Silver nanoparticles to fight Candida coinfection in the oral cavity

[Exert] This chapter is focused on the activity of silver nanoparticles (SN) as an antifungal agent against Candida albicans and Candida glabrata biofilms, which are involved in oral candidosis. A discussion focusing on the influence of the stabilizing agent, diameter of SN on its antibiofilm activity, influence of chemical stability of SN on Candida biofilms, the effect of SN against adhered cells and biofilms, the effect on extracellular matrix composition and structure of Candida biofilms, the combination of SN with conventional antifungal drugs, and the incorporation of SN into denture acrylic resin is incorporated in the present chapter. Because of the resistance of Candida biofilms to conventional drugs and the positive effect of SN against them, these nanoparticles can be used as an alternative antifungal agent (...).

Use of tandem stents for treatment of helicoidal dissection of the right coronary artery

Coronary dissection occurs frequently and in several degrees during coronary angioplasty, which is one of the mechanisms for increasing the lumen diameter of a vessel. However the length of the dissection may affect the procedure, becoming the most frequent cause of total occlusion after coronary angioplasty. We report here a case of extensive dissection that occurred during the coronary angioplasty of a focused lesion, which we treated with two long stents.

Structural and functional characteristics of rat hearts with and without myocardial infarct. Initial experience with doppler echocardiography

OBJECTIVE: To assess by Doppler echocardiography the structural and functional alterations of rat heart with surgical induced extensive myocardial infarction. METHODS: Five weeks after surgical ligature of the left coronary artery, 38 Wistar-EPM rats of both sexes, 10 of them with extensive infarction, undergone anatomical and functional evaluation by Doppler echocardiography and then euthanized for anatomopathological analysis. RESULTS: Echocardiography was 100% sensible and specific to anatomopathological confirmed extensive miocardial infarction. Extensive infarction lead to dilatation of left ventricle (diastolic diameter: 0.89cm vs.0.64cm; systolic: 0.72cm vs. 0.33cm) and left atrium (0.55cm vs. 0.33cm); thinning of left ventricular anterior wall (systolic: 0.14cm vs. 0.23cm, diastolic: 0.11cm vs. 0.14cm); increased mitral E/ A wave relation (6.45 vs. 1.95). Signals of increased end diastolic ventricle pressure, B point in mitral valve tracing in 62.5% and signs of pulmonary hypertension straightening of pulmonary valve (90%) and notching of pulmonary systolic flow (60%) were observed in animals with extensive infarction. CONCLUSION: Doppler echocardiography has a high sensitivity and specificity for detection of chronic extensive infarction. Extensive infarction caused dilatation of left cardiac chambers and showed in Doppler signals of increased end diastolic left ventricular pressure and pulmonary artery pressure.

A comparative analysis of primary stenting and optimal balloon coronary angioplasty in acute myocardial infarction. Six month results from the STENT PAMI trial

OBJECTIVE: To compare the outcome of balloon PTCA with final coronary stenosis diameter (SD) <=30%, with elective coronary stenting. METHODS: We performed a comparative analysis of the 6 month outcomes in patients treated with primary stenting and those who obtained an optimal balloon PTCA result treated during the first 12 hours of AMI onset included in the STENT PAMI randomized trial. RESULTS: The results were analysed into 3 groups: primary stenting (441 patients, SD=22±6%), optimal PTCA (245 patients), and nonoptimal PTCA (182 patients, SD= 37±5%). At the end of the 6 months primary stent group presented with the lowest restenosis(23 vs. 31 vs. 45%, p=0.001, respectively). Ischemia-driven target vessel revascularization rate (TVR) (7 vs. 15.5 vs. 19%, p=0.001, respectively). CONCLUSION: At the 6 month follow-up, primary stenting offered the lowest restenosis and ischemia-driven TVR rates. Compared to optimal balloon PTCA. Nonoptimal primary balloon PTCA pts (SD=31-50%), had the worst late angiographic outcomes and should be treated more actively with coronary stent implantation.

The use of primary stenting or balloon percutaneous transluminal coronary angioplasty for the treatment of acutely occluded saphenous vein grafts. Results from the Brazilian National Registry - CENIC

OBJECTIVE: We conducted a comparative analysis of the in-hospital outcomes of patients who underwent primary percutaneous transluminal angioplasty (PTCA) or stent implantation because of an acute myocardial infarction (AMI) related to an acute vein graft occlusion. METHODS: Since 1991 the Brazilian Society of Hemodynamic and Interventional Cardiology has maintained a large database (CENIC). From these, we selected all consecutive patients, who underwent primary PTCA or stenting in the first 24 hours of AMI, with the target vessel being an occluded vein graft. Immediate results and major coronary events occurring up until hospital discharge were analyzed. RESULTS: During this period, 5,932 patients underwent primary PTCA or stenting; 158 (3%) of the procedures were performed because of an acute vein graft occlusion. Stenting was performed in 74 (47%) patients. Patients treated with stents had a higher success rate and lower mean residual stenosis compared with those who underwent primary balloon PTCA. The incidence of reinfarction and death were similar for stenting and balloon PTCA. CONCLUSION: Primary percutaneous treatment of AMI related to acute vein graft occlusion is still an uncommon practice. Primary stenting improved luminal diameter and offered higher rates of success; however, this strategy did not reduce the in-hospital reinfarction and death rate, compared with that occurring with PTCA treatment.

Use of transesophageal echocardiography during implantation of aortic endoprosthesis (stent). Initial experience

OBJECTIVE: To report the role played by transesophageal echocardiography during implantation of self-expanding aortic endoprostheses (stent) at a hemodynamics laboratory. METHODS: Thirteen patients underwent stent implantation in the descending thoracic aorta with the aid of transesophageal echocardiography during the entire procedure. Indications for stenting were as follows: 8 aortic dissections, 2 true aneurysms, 2 penetrating atherosclerotic ulcers, and 1 traumatic pseudoaneurysm. RESULTS: No complications resulting from the use of transesophageal echocardiography were observed. In 12 patients, the initial result was considered appropriate, with total or partial resolution of the major lesion confirmed by a posterior examination. In 1 patient, the procedure was suspended after transesophageal echocardiography and angiography showed that the proximal aortic diameter was inappropriate. Transesophageal echocardiography contributed to clarifying relevant points, such as aortic diameter, anatomic detail of the intimal lesion, and location and size of the communicating orifice. In addition, it facilitated placing the stent in the target lesion, reduced the time of exposure to radiation and the use of contrast medium, and provided rapid identification of intercurrent events, possibly reducing the total duration of the procedure. CONCLUSION: The use of transesophageal echocardiography during placement of aortic stents seems appropriate. The actual advantages of the procedure will be defined in a comparative prospective study.

Percutaneous closure of ductus arteriosus with the amplatzer prosthesis. The Brazilian experience

OBJECTIVE - To report the results of percutaneous occlusion of persistent ductus arteriosus with the Amplatzer prosthesis in 2 Brazilian cardiological centers. METHODS - From May 1998 to July 2000, 33 patients with clinical and laboratory diagnosis of persistent ductus arteriosus underwent attempts at percutaneous implantation of the Amplatzer prosthesis. The median age was 36 months (from 6 months to 38 years), and the median weight was 14kg (from 6 to 92kg). Sixteen patients (48.5%) were under 2 years of age at the time of the procedure. All patients were followed up with periodical clinical and echocardiographic evaluations to assess the presence and degree of residual shunt and possible complications, such as pseudocoarctation of the aorta and left pulmonary artery stenosis. RESULTS - The minimum diameter of the arterial ducts ranged from 2.5 to 7.0mm (mean of 4.0±1.0, median of 3.9). The rate of success for implantation of the prosthesis was 100%. Femoral pulse was lost in 1 patient. The echocardiogram revealed total closure prior to hospital discharge in 30 patients, and in the follow-up visit 3 months later in the 3 remaining patients. The mean follow-up duration was 6.4±3.4 months. All patients were clinically well, asymptomatic, and did not need medication. No patient had narrowing of the left pulmonary artery or of the aorta. No early or late embolic events occurred, nor did infectious endarteritis. A new hospital admission was not required for any patient. CONCLUSION - The Amplatzer prosthesis for persistent ductus arteriosus is safe and highly effective for occlusion of ductus arteriosus of varied diameters, including large ones in small symptomatic infants.

Reversibility of ventricular dysfunction: clinical experience in a medical office

OBJECTIVE - To describe clinical observations of marked improvement in ventricular dysfunction in a medical office environment under circumstances differing from those in study protocols and multicenter studies performed in hospital or with outpatient cohorts. METHODS - Eleven cardiac failure patients with marked ventricular dysfunction receiving treatment at a doctors office between 1994 and 1999 were studied. Their ages ranged from 20 and 66 years (mean 39.42±14.05 years); 7 patients were men, 4 were women. Cardiopathic etiologies were arterial hypertension in 5 patients, peripartum cardiomyopathy in 2, nondefined myocarditis in 2, and alcoholic cardiomyopathy in 4. Initial echocardiograms revealed left ventricular dilatation (average diastolic diameter, 69.45±8.15mm), reduced left ventricular ejection fraction (0.38±0.08) and left atrial dilatation (43.36±5.16mm). The therapeutic approach followed consisted of patient orientation, elimination of etiological or causal factors of cardiac failure, and prescription of digitalis, diuretics, and angiotensinconverting enzyme inhibitors. RESULTS - Following treatment, left ventricular ejection fraction changed to 0.63±0.09; left ventricular diameters changed to 57.18±8.13mm, and left atrium diameters changed to 37.27±8.05mm. Maximum improvement was noted after 16.9±8.63 (6 to 36) months. CONCLUSION - Patients with serious cardiac failure and ventricular dysfunction caused by hypertension, alcoholism, or myocarditis can experience marked improvement in ventricular dysfunction after undergoing appropriate therapy within the venue of the doctor's office.

Ambulatory blood pressure monitoring of patients with heart failure: a new prognosis marker

OBJECTIVE: To evaluate the relationship between 24-hour ambulatory arterial blood pressure monitoring and the prognosis of patients with advanced congestive heart failure. METHODS: We studied 38 patients with NYHA functional class IV congestive heart failure, and analyzed left ventricular ejection fraction, diastolic diameter, and ambulatory blood pressure monitoring data. RESULTS: Twelve deaths occurred. Left ventricular ejection fraction (35.2±7.3%) and diastolic diameter (72.2±7.8mm) were not correlated with the survival. The mean 24-hour (SBP24), waking (SBPw), and sleeping (SBPs) systolic pressures of the living patients were higher than those of the deceased patients and were significant for predicting survival. Patients with mean SBP24, SBPv, and SBPs > or = 105mmHg had longer survival (p=0.002, p=0.01 and p=0.0007, respectively). Patients with diastolic blood pressure sleep decrements (dip) and patients with mean blood pressure dip <=6mmHg had longer survival (p=0.04 and p=0.01, respectively). In the multivariate analysis, SBPs was the only variable with an odds ratio of 7.61 (CI: 1.56; 3704) (p=0.01). Patients with mean SBP<105mmHg were 7.6 times more likely to die than those with SBP > or = 105 mmHg CONCLUSION: Ambulatory blood pressure monitoring appears to be a useful method for evaluating patients with congestive heart failure.

Development of nanohydrogels as a vehicle for the release of bioactive compounds in food matrices

PhD in Chemical and Biological Engineering

Combustion of alternative biomass fuels in a domestic boiler and in a large-scale furnace

Programa Doutoral em Engenharia Mecânica.

Myocardial Bridges and their Relationship to the Anterior Interventricular Branch of the Left Coronary Artery

OBJECTIVE: To analyze the relationship between myocardial bridges and the anterior interventricular branch (anterior descending) of the left coronary artery. METHODS: The study was carried out with postmortem material, and methods of dissection and observation were used. We assessed the perimeter of the anterior interventricular branch of the left coronary artery using a pachymeter, calculated its proximal and distal diameters in relation to the myocardial bridge, and also its diameter under the myocardial bridge in 30 hearts. We also observed the position of the myocardial bridge in relation to the origin of the anterior interventricular branch. RESULTS: The diameters of the anterior interventricular branch were as follows: the mean proximal diameter was 2.76±0.76 mm; the mean diameter under the myocardial bridge was 2.08±0.54 mm; and the mean distal diameter was 1.98±0.59 mm. In 33.33% (10/30) of the cases, the diameter of the anterior interventricular branch under the myocardial bridge was lower than the diameter of the anterior interventricular branch distal to the myocardial bridge. In 3.33% (1/30) of the cases, an atherosclerotic plaque was found in the segment under the myocardial bridge. The myocardial bridge was located in the middle third of the anterior interventricular branch in 86.66% (26/30) of the cases. CONCLUSION: Myocardial bridges are more frequently found in the middle third of the anterior interventricular branch of the left coronary artery. The diameter of the anterior interventricular branch of the left coronary artery under the myocardial bridge may be smaller than after the bridge. Myocardial bridges may not provide protection against the formation of atherosclerotic plaque inside the anterior interventricular branch of the left coronary artery.

Benefits of exercise training in the treatment of heart failure: study with a control group

OBJECTIVE: Exercise training programs have been proposed as adjuncts to treatment of heart failure. The effects of a 3-month-exercise-training-program with 3 exercise sessions per week were assessed in patients with stable systolic chronic heart failure. METHODS: We studied 24 patients with final left ventricle diastolic diameter of 70±10mm and left ventricular ejection fraction of 37±4%. Mean age was 52±16 years. Twelve patients were assigned to an exercise training group (G1), and 12 patients were assigned to a control group (G2). Patients underwent treadmill testing, before and after exercise training, to assess distance walked, heart rate, systolic blood pressure, and double product. RESULTS: In G2 group, before and after 3 months, we observed, respectively distance walked, 623±553 and 561± 460m (ns); peak heart rate, 142±23 and 146± 33b/min (ns); systolic blood pressure, 154±36 and 164±26 mmHg (ns); and double product, 22211± 6454 and 24293±7373 (ns). In G1 group, before and after exercise, we observed: distance walked, 615±394 and 970± 537m (p<0.003) peak heart rate, 143±24 and 143±29b/min (ns); systolic blood pressure, 136±33 and 133±24 mmHg (ns); and double product, 19907± 7323 and 19115±5776, respectively. Comparing the groups, a significant difference existed regarding the variation in the double product, and in distance walked. CONCLUSION: Exercise training programs in patients with heart failure can bring about an improvement in physical capacity.