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Piotr Podolec

Publications and source records attributed to Piotr Podolec.

At least 55 records · Page 3Linked to original sources
PubMed2004

[Echocardiographic prediction of outcome in patients with congestive heart failure and mitral regurgitation].

BACKGROUND: Congestive heart failure is associated with the increase risk of death or cardiac transplantation. The ability of current techniques to predict outcome in heart failure is rather limited. Identification of the patients at risk of cardiac death or requiring heart transplantation is clinically important. The changing rate of left ventricular pressure during the cardiac cycle is an important parameter in the assessment of myocardial systolic function. Non-invasive echocardiographic method--dP/dt has been proposed to determine the isovolumic phase of cardiac function. The aim of this study was to evaluate the ability of Doppler-derived dP/dt to predict survival in patients with congestive heart failure. MATERIAL AND METHODS: Thirty one patients (22M, 9W), mean age 55 +/- 11.2 years, with CHF (LVEF < 45%, NYHA II-IV class) and chronic mitral regurgitation were analyzed. The echocardiography, cardiopulmonary exercise test and clinical follow-up were performed in all of them. The ejection fraction was calculated using the Simpson's method from apical 4-chamber view. The dP/dt index was derived from the continuous-wave Doppler spectrum. The mean follow-up period was 28.5 +/- 12 months. According to the clinical status the patients were divided into two groups: group I--21 event-free patients and group II--10 patients who experienced primary events (5 died and 5 underwent heart transplantation). RESULTS: In the group of primary events patients there was noted a significant decrease of the dP/dt index in comparison to the event-free patients: 463 mmHg/s vs 839 mmHg/s (p=0.0001). The correlation between dP/dt and ejection fraction, left ventricular end-diastolic diameter as well as between the parameters of cardiopulmonary exercise test VO2peak, VO2AT, VE/VCO2peak was found. CONCLUSIONS: Doppler echocardiographic index of dP/dt can predict the outcome in patients with congestive heart failure. Dp/dt can be useful as a prognostic factor in patients with CHF. A significant correlation was observed between dP/dt and VO2peak as well as VE/VCO2peak which are independent prognostic predictors.

Adult↗
PubMed2004

[Relationship between Doppler indices of diastolic function and exercise capacity in patients with congestive heart failure].

UNLABELLED: Exercise intolerance is a major symptom in patients (pts) with congestive heart failure (CHF). A lack of correlation between the left ventricular systolic dysfunction and exercise capacity was found. Recently, it has been proposed that diastolic dysfunction may contribute to significant impairment of exercise tolerance in pts with CHF. The aim of the study was to compare the relationship between Doppler indices of diastolic function and exercise capacity in patients with CHF. MATERIAL AND METHODS: The study included 29 pts (20 M, 9 F) 14 with idiopathic and 15 with ischaemic cardiomyopathy. The mean left ventricular ejection fraction (LVEF) was 31 +/- 8%, VO2peak was 16.4 +/- 4.6 ml/kg/min. The mean age was 55.4 +/- 12.1, ranged from 30 to 73 years. All pts underwent complete echocardiography study. Diastolic performance was estimated using conventional Doppler mitral inflow (E, A) velocities, E/A ratio, deceleration time of E velocity (E-DT), isovolumetric relaxation time (IVRT) and color Doppler M-mode flow propagation velocity (Vp). Resting spirometry and cardiopulmonary exercise test (CPX) were performed in all pts. Exercise capacity was measured as oxygen consumption at peak exercise (VO2peak). The association between echocardiography parameters and VO2peak was evaluated by Spearman's correlation coefficients (r). RESULTS: We found that VO2peak correlated significantly with the LV filling pattern estimated by the transmitral Doppler E/A ratio (r=-0.4, p=0.03), A-wave velocity (r=0.4, p=0.03) and velocity flow propagation (r=0.4, p=0.05). There was no correlation between VO2peak and following mitral inflow parameters: (E-wave, DT, IVRT). There was no correlation between VO2peak and LVEF. CONCLUSIONS: 1. Doppler indices of diastolic function are important determinants of exercise capacity in CHF pts. 2. Assessment of transmitral flow velocities holds a substantial diagnostic potential, which may be utilized in everyday clinical practice as a alternative in routine monitoring of systolic heart failure.

Adult↗
PubMed2004

[Assessment of ejection fraction by cardiovascular magnetic resonance in comparison with 99mTc gated SPECT].

BACKGROUND: Impaired left ventricular (LV) function with decreased ejection fraction (EF) is a frequent finding in patients with ischaemic heart disease. As a non-invasive method, cardiovascular magnetic resonance (CMR) has become an important diagnostic method in cardiology within the past decade, especially for assessing myocardial function. AIM: The purpose of this study is to compare EF estimated with 99mTc gated SPECT (GSPECT) and with CMR. METHODS: The study was performed in a group of 35 patients (11 F, 24 M; mean age 57 SD 10) after myocardial infarction. EF in CMR procedure was calculated using cine gradient echo sequences. GSPECT measured EF was estimated by Tc 99. RESULTS: The mean value of EF measured with scintigraphy was 50.5 +/- 17%, and measured with CMR 48.3 +/- 15%. The difference in mean values of EF was not statistically significant. CONCLUSIONS: 1. EF in CMR was highly concordant with GSPECT. 2. The mean value of EF measured with CMR in 75% of study patients was smaller than in the scintigraphy group, but the difference was not statistically significant. 3. CMR is a simple, precise and reproducible diagnostic method for monitoring left ventricle systolic function, and which is an additional non-invasive imaging technique in cardiac diagnosis.

Adult↗
PubMed2004

[Morphology and location of atherosclerotic lesions in coronary vessels depending on gender and age].

Coronary artery disease is a major social problem. However, its epidemiology, pathophysiology, clinical course, diagnostic efficiency and therapeutic potential differ significantly with regard to gender and age. There are few comparative data available on morphological differences and immediate results of direct percutaneous interventions, aorto-coronary bypass grafting, complication rate, risk factors for developing complications after invasive procedures in CAD patients of both sexes and in various age groups. The aim of the study was to identify differences in the location and morphology of coronary plaque and left ventricular function in CAD patients with regard to gender and age. The study included consecutive patients with coronary artery disease diagnosed and treated in the Department of Hemodynamics and Angiocardiography Jagiellonian University Medical College from June 1997 to June 1998. Coronary angiography group, consisting of 1374 patients, 1004 men (73.1%) and 370 women (26.9%), of whom 1146 (83.4%), 890 men (77.7%) and 256 women (22.3%), were included in the final morphological and clinical analysis and in whom coronary angiography confirmed the presence of coronary plaque. The subgroups were further subdivided into two age groups: below and over 50 years of age. Clinical, angiographic and hemodynamic data were analysed retrospectively. Analysis revealed that among patients after invasive diagnosis because of suspected coronary artery disease atherosclerotic lesions in epicardial coronary vessels were significantly more frequently confirmed in men. In patients of both sexes the proportion of patients with angiographically confirmed lesions rises with age. In patients with angiographically documented coronary artery diseases the location and morphology of stenosis in epicardial coronary vessels differs between sexes in the corresponding age groups. Left ventricular function is better preserved in women.

Adult↗
PubMed2004

[Comparison of myocardial perfusion assessed by Tc99m MIBI single photon emission computer tomography (SPECT) with the Coronary Calcium Score (CS) assessed by multi-slice computer tomography (MSCT)].

BACKGROUND: There is growing evidence regarding evaluation of Coronary Artery Calcium Score (CS) using the multi-slice computer tomography (MSCT), but as a new method it still need for verification in comparison with other, non-invasive modalities, with established rationale. One of these is SPECT, which value in evaluation of patients with coronary artery disease is well known. We tried to compare these two studies and their usefulness in diagnosis of patients with confirmed coronary artery disease. MATERIAL AND METHODS: 72 patients (53 males and 19 females, mean age 59.9 +/- 8.66), all after coronary angiography, with coronary artery disease (CCS II or III) were included into our study. SPECT and exercise treadmill results were compared with the coronary artery calcium score (CS) as assessed by MSCT. Both studies were performed with maximal 7-days intervals at most between the studies. Image reconstruction was performed using the Autoperfusion protocol, with the VISUAL Score analysis (5-point scale) of extent of perfusion defect. MSCT was evaluated using the Calcium Score protocol. For the statistical analysis we used Student's T-test and Pearson correlation analysis. RESULTS: The correlation between total CS and the score of the reversible and non-reversible perfusion defects in Tc 99mMIBI SPECT was not found. Following the analysis for the 3 main coronary arteries separately, and number of perfusion defects, a correlation was observed for LAD and RCA perfusion regions. CONCLUSIONS: 1. Statistically significant correlation between CS by MSCT and SPECT perfusion deficiencies in the left descending artery (LAD) and right coronary artery (RCA) perfusion regions were found. 2. The correlation between high CS (>400) and the presence of hemodynamically significant changes in coronary angiography was found. 3. We conclude that CS by MSCT may be a screening-tool of some value for risk stratification.

Aged↗
PubMed2004

[Left ventricular systolic function in patients with refractory angina pectoris treated with percutaneous myocardial laser revascularisation, results of long-term follow-up].

INTRODUCTION: Percutaneous myocardial laser revascularisation (PMLR) has been developed for treatment of patients with refractory angina pectoris. This study was designed to evaluate long-term impact of PMLR on left ventricular systolic function. MATERIAL AND METHODS: Ten patients with refractory angina pectoris who underwent PMLR were studied with dobutamine stress echocardiography before procedure, at early follow-up after 1-3 months and at long-term follow-up after 2-3 years post procedure. Wall motion score index (WMSI) and ejection fraction (EF) were calculated at rest as well during infusion of dobutamine with low and high rate. RESULTS: Mean WMSI at rest decreased significantly from 1.71 +/- 0.24 before PMLR to 1.55 +/- 0.21 at early follow-up (p=0.0189) and 1.48 +/- 0.26 (p=0.009) at long-term follow-up. Mean WMSI during low-rate dobutamine infusion decreased significantly from 1.39 +/- 0.29 to 1.25 +/- 0.25 (p=0.0276) at early follow-up, but was not significantly different in long-term. Mean WMSI during high-rate dobutamine infusion decreased significantly from 1.83 +/- 0.21 before PMLR to 1.56 +/- 0.2 at early follow-up and 1.57 +/- 0.29 (p<0.03) at long-term evaluation. Mean EF at rest increased significantly from 48 +/- 8.6% before PMLR to 56.9 +/- 7.9% (p=0.0189) at early follow-up. At long-term follow-up mean EF at rest was 52.7 +/- 8.3% and was not significantly different from baseline. Mean EF during low-rate dobutamine infusion was not significantly different from baseline both at early and long-term follow-up. Mean EF during high-rate dobutamine infusion increased significantly from 44.5 +/- 8.6% before PMLR to 58.1 +/- 7.0% (p=0.0093) at early follow-up while in long-term it was 51.3 +/- 9.8%, which was not significantly different from baseline. These changes were accompanied by significant decrease of mean CCS score from 3.52 +/- 0.51 before procedure to 2.54 +/- 0.78 (p<0.0001) after 1 month and 2.78 +/- 0.65 after 24 months. CONCLUSIONS: In patients with refractory angina pectoris treated with PMLR significant early improvement of systolic left-ventricular function is observed with trend toward improvement in long-term. It is accompanied with significant long-term angina relief.

Aged↗
PubMed2004

[Right ventricular infarction: novel modalities of treatment].

Acute right ventricular infarction (RVI) is usually caused by proximal occlusion of the right coronary artery. RVI is frequent, as it occurs in as many as one out of every two left ventricular interior and/or posterior wall infarctions. The involvement of the right ventricle in acute myocardial infarction has been shown to be associated with an increased risk of life-threatening arrhythmias and sudden cardiac death. Clinical course of RVI can vary from being completely silent to cardiogenic shock (seen in 10-15% patients with inferior wall infarction). RVI diagnosis is based on clinical signs (hypotension and increased jugular venous pressure while pulmonary fields are clear), ECG (ST elevation by > or = 1 mm in V4R), echocardiography (right ventricular wall regional motion abnormalities and/or right ventricle distension, paradoxical motion of the interventricular septum, tissue Doppler), technetium pyrophosphate scanning with ventriculography, and invasive patient monitoring. In addition to its important diagnostic part, the invasive patient monitoring plays a key role in risk stratification and can dynamically guide the treatment (such as fluid loading). In most cases, successful reperfusion in the infarct-related artery territory can be achieved by interventional management (i.e. angioplasty) or--if the latter is not available--by thrombolytic therapy. Patients with arterial hypotension require volume expansion which is best guided by the central venous pressure (CVP; a measure of the right atrial pressure, RAP) and the pulmonary capillary wedge pressure (PCWP). If the hemodynamics does not improve despite optimal fluid loading, pharmacological (catecholamine infusion) or mechanical (intra-aortic balloon pump) circulatory assistance needs to be implemented. Patients with significant sinus bradycardia or 3rd degree AV block may require temporary cardiac pacing. In addition, inhalatory nitric oxide (iNO) has been shown to reduce right ventricular afterload in a selective manner and its potential clinical role is currently being evaluated. Within several months after RVI, the right ventricular performance improves in most patients, including those without successful reperfusion of IRA. Such patients, however, have an increased risk of complications (including sudden death) while the recovery of right ventricular function is slow.

Angioplasty, Balloon, Coronary↗
PubMed2004

[Vasodilatator testing with nitric oxide (bronchial control treatment system--BCTS) in patients with pulmonary hypertension].

Nitric oxide (NO) is one of the most important mediators produced in the human organism. It participates in the regulation of blood vessel lumens, activation of leucocytes and platelet; it is a mediator in the nervous system and in inflammation reactions. It was proved that in cases of patients with pulmonary hypertension, a decreased secretion of nitric oxide and an increased synthesis of endothelin-1 is observed. Therefore, in case of patients with pulmonary hypertension the exogenous, inhaled nitric oxide (iNO) is applied. It is added to the respiratory mixture and it passes through the alveolar-capillary barrier to the smooth muscle cells where it activates a guanyle cyclase, similarly to the physiologically produced nitric oxide. It was proved that it decreases pulmonary vascular resistance (PVR) and pulmonary artery pressure (PAP). Inhaled nitric oxide is applied for treatment purposes to patients after cardiosurgical operations, mainly heart transplantation and correction of valvular defects with accompanying pulmonary hypertension, as well as after implantation of the left ventricular assist device in order to relieve the right chamber. In case of patients qualified for cardiosurgical operations with the accompanying pulmonary hypertension as well as in case of patients with the arterial pulmonary hypertension a diagnostical test using iNO is carried out in order to determine further course of therapeutical treatment. The application of the new method of iNO administration by the BCTS (Bronchial Control Treatment System) method allows for a precise administration of accurately determined doses of iNO and its full utilisation through addition to the respiratory mixture in the initial phase of inspiration. The risk of side effects is also decreased; so far no influence on the circulatory system or an increase of the level of methemoglobin was observed.

Administration, Inhalation↗
PubMed2004

The degree of restored myocardial perfusion in acute myocardial infarction influences immediate and long-term results of primary coronary angioplasty.

BACKGROUND: Tissue perfusion during acute myocardial infarction (AMI) may be assessed by means of the angiographic method -- TIMI myocardial perfusion (TMP). We hypothesised that TMP grade (TMPG) after primary coronary angioplasty (PCI) implicates immediate and long-term clinical outcomes. METHODS: We studied 588 consecutive patients (mean age 58.7+/-10.8 years) with ST-segment elevation AMI treated with PCI. Infarct-related TMPG was evaluated before and after PCI. Myocardial injury was expressed as an area under the curve (AUC) of CK-MB release in the first 48 hours of reperfusion. Left ventricular ejection fraction (LVEF) was assessed by 2-dimensional echocardiography one day after PCI. Clinical end-points during a 12-month follow-up included death, recurrent MI and repeated revascularisation or hospitalisation. At the end of the follow-up, NYHA functional class was evaluated in all patients. RESULTS: Before PCI, TMPG -3, -2 and -0/1 values were observed in 52 (8.8%), 77 (13.1%) and 459 (78.1%) patients, respectively. After PCI, TMPG-3, -2 and -0/1 were achieved in 196 (33.3%), 174 (29.6%) and 218 (37.1%) patients, respectively. Patients with TMPG-3, -2, and -0/1 had AUC of 10341+/-1194, 12330+/-1272 and 16718+/-1860 (U/l x h) (p<0.01) and LVEF of 53.6+/-8.6%, 45.5+/-9.5% and 41.7+/-10.4% (p<0.001), respectively. In-hospital mortality rate in patients with TMPG-3, -2 and -0/1 was 0%, 4% and 11.9%, respectively (p<0.001), and after 12-months - 2%, 6.3% and 16.5%, respectively (p<0.001). The event-free survival rate after 1-year was 83.2%, 74.1% and 65.1% respectively (p<0.001). The percentage of patients in NYHA class > or =2 was 10.2%, 16.1% and 20.6% (p=0.003), respectively. CONCLUSIONS: The TIMI myocardial perfusion grade after primary coronary angioplasty in acute myocardial infarction effects left ventricular injury and function as well as early and long-term clinical outcome.

Angioplasty, Balloon, Coronary↗
PubMed2003

Reoperation after fresh homograft replacement: 23 years' experience with 655 patients.

OBJECTIVE: Through a retrospective study on the use of fresh homografts in 655 aortic valve replacement patients over a period of 23 years, we aimed to assess the reasons for eventual reoperation and causes of valve dysfunction. METHODS: Between January 1980 and December 2002, 655 patients received fresh homografts. All homografts were antibiotic sterilized and stored at 4 degrees C. During this time, 139 patients (116 male and 23 female) with a mean age of 46.7 years (range 18-72) required reoperation. RESULTS: The 30-day hospital overall mortality was 2.87%. The mean durability for all homografts was 12.4+/-4.54 years (1 month to 23 years). The cumulative rates for freedom from reoperation for any cause were 94.09+/-2% at 5 years and 87.9%+/-4% at 10 years, 76.6 at 15 years, 49.55 at 20 years. The major cause of valve dysfunction and indication for reoperation was degeneration in 111 patients (79.8%). Predominant aortic valve insufficiency in 87 patients (62.5%) and predominant stenosis in 24 patients (17.26%). Endocarditis occurred in 21 patients (15.1%). Early endocarditis was diagnosed in five patients (3.59%), late endocarditis in 16 patients (11.5%). Additional causes for reoperation included ascending aortic aneurysm, mitral valve insufficiency and congestive cardiomyopathy. Seventeen patients (12.2%) required concomitant procedures. Coronary artery bypass grafting was performed in six cases (4.3%), mitral valve replacement in five cases (3.59%), mitral valve annuloplasty in six (4.3%). The primary reoperative procedure was artificial/mechanical aortic valve implantation. In five cases, St. Jude Medical conduit grafts were implanted due to ascending aortic aneurysms. Homograft reimplantation was performed in four cases. One patient underwent mitral valve replacement and one patient received a heart transplant. CONCLUSION: The results of the study suggest that reoperation in patients with aortic homografts is a low-risk procedure as compared to alternative therapies. Primary allograft aortic valve replacement can give acceptable results for up to 23 years. The major cause of valve dysfunction and indication for reoperation was degeneration. Cumulative rates for freedom from reoperation for any cause in age groups suggest careful selection and indications in homograft implantation in the younger patients. Young age is a risk factor for an early homograft structural deterioration (degeneration).

Adolescent↗
PubMed2003

Prognostic value of nitrate enhanced Tc99m MIBI SPECT study in detecting viable myocardium in patients with coronary artery disease.

BACKGROUND: Assessing the viability in akinetic myocardium is vital for predicting functional recovery after therapeutic management in patients with chronic coronary artery disease (CAD) and depressed left ventricular (LV) function. The present study aimed to evaluate the efficacy of Tc99m MIBI SPECT enhanced with nitroglycerine infusion in detecting myocardial viability, as well as to asses the relationship between the myocardial viability and the subsequent treatment and outcome of patients. METHODS AND RESULTS: Sixty-seven consecutive patients with CAD and LV dysfunction (LV ejection fraction 36.6 +/- 8.4%) underwent Tc99m MIBI imaging--at rest and during intravenous nitroglycerine infusion--for viability assessment. Fourteen patients were treated pharmacologically (Group I), and fifty-three (Group II) were submitted to coronary revascularization (PTCR or CABG). Fifteen major cardiac events were observed during 25 months of the follow-up. A significantly worse event-free survival was registered in the subjects of Group I than in Group II subjects. The prognostic predictors of cardiac events were: (1) the number of viable, non-revascularized segments in perfusion imaging (p < 0.001), (2) the severity of the disease assessed by coronary angiography (p < 0.05). CONCLUSIONS: Viability detection in nitroglycerine infusion enhanced Tc99m MIBI imaging offers significant prognostic value in patients with CAD after myocardial infarction. Patients with preserved viability showed better prognosis after revascularization than those treated pharmacologically.

Coronary Artery Disease↗
PubMed2003

Myocardial ischemia assessed by Tc99m MIBI SPECT and left ventricle regional systolic and diastolic function evaluated by tissue Doppler echocardiography.

BACKGROUND: Tc99m MIBI single-photon emission computed tomography (SPECT) study facilitates the evaluation of the regional myocardial perfusion and tissue Doppler echocardiography imaging facilitates the quantitative assessment of the regional systolic and diastolic function of the myocardium. The aim of the study was an assessment of the correlation between regional rest myocardial perfusion defects and regional rest systolic and diastolic myocardial velocities in patients with ischemic heart disease (IHD). MATERIAL AND METHODS: In 40 IHD patients (33 men, 7 women) aged 43-74 years (mean 56 years) rest SPECT imaging with Tc99m MIBI and rest tissue Doppler examinations were performed. The control group consisted of 35 healthy sex and age matched pesons. The left ventricle was divided into 13 segments. The number of non-perfused segments in three myocardial perfusion regions (left anterior descending artery, circumflex artery, right coronary artery) was assessed in IHD patients. During tissue Doppler examination the maximal systolic and maximal early diastolic velocity of the myocardium in each segment were established in both examined groups. RESULTS: The systolic and diastolic myocardial velocities were significantly lower in IHD group as compared to control group. In the IHD group statistically significant decrease of systolic and diastolic velocities in relation to the number of non-perfused segments was found. In comparing the linear regression slopes for systolic and for diastolic myocardial velocities in terms of intensification of perfusion defects, a more pronounced decrease in diastolic velocity was encountered. CONCLUSIONS: Both systolic and diastolic myocardial velocities are decreased in the myocardial regions with perfusion defects, but the reduction of the diastolic velocity is higher than the reduction of the systolic velocities. Thus our results indicate a good correlation between the intensity of perfusion abnormalities and myocardial velocities. The levels of diastolic dysfunction is more pronounced than the level of systolic dysfunction in the ischemic myocardium.

Adult↗
PubMed2003

Impact of Chlamydia pneumoniae infection on survival rate after heart transplantation.

BACKGROUND: As Chlamydia pneumoniae (Cp), a common cause of respiratory infection, is of vasotropic character, chronic infection may be associated with the development of coronary disease, although there have been few reports on the impact of Cp infection on the post-orthotopic heart transplantation (OHT) survival rate. MATERIAL/METHODS: A total of 41 patients (4 females) were followed up for one year after OHT. Serology investigations for IgM, IgG and IgA antibodies against Cp were performed using the enzyme immunoassay (EIA) method. Univariate and multivariate analyses were carried out with respect to IgA, IgG, gender and type of cardiomyopathy. The IgA-IgG joint effect was also studied. RESULTS: The one-year survival rate was reported for patients with IgA < 8 EIU to be 72.2%, whereas those with IgA >or= 8 EIU accounted for only 43.5% (Kaplan-Meier analysis, p = 0.0548). In multivariate analysis IgA /IgG status proved to be a highly significant factor in survival. IgA positive outcome combined with IgG negative outcome showed that the relative risk of death equaled 12.08 versus other combinations of IgA/IgG status. In the Cox multivariate model ischemic cardiomyopathy showed a relative risk of 2.79 (p=0.0594), although it was not significant in univariate CONCLUSIONS: Chronic Cp infection, as expressed through a high IgA level, seems to have adverse impact on the survival rate in one-year follow-up after OHT. IgA titers against Cp in heart transplant recipients should therefore be assessed, as the high values might be a predictive risk factor within the first post-operative year.

Adult↗
PubMed2003

Mineralization and organic phase modifications as contributory factors of accelerated degeneration in homograft aortic valves.

BACKGROUND AND AIM OF THE STUDY: The study aim was to assess histological and mineralogical properties of leaflets in human, antibiotic-preserved aortic homograft valves (recovered during surgical replacement) in order to identify factors accounting for pathological changes leading to accelerated graft dysfunction. A comparison was made with aortic valves prepared for grafting, with a view to assessing morphological and mineralogical characteristics as a potential preimplantation risk factor. METHODS: Valve leaflets were examined with light and scanning electron microscopy. Mineralization was assessed histochemically, and also physicochemically by atomic absorption spectroscopy (AAS). RESULTS: All explanted homograft valve leaflets revealed prominent degenerative changes seen as decreased surface area, fibrosis, mineralization and focal thrombosis. Substantial loss of endothelium and fibroblasts, reduced collagen bundles crimping, inflammation (81%) and disappearance of layered structure (59%) was identified. The elastic elements were relatively stable, though a gradual age-dependent loss was observed in both groups. Accelerated mineralization was seen in all explanted homografts; inorganic deposits were composed mainly of hydroxyapatite. Two types of mineralization were identified: large limited nodular structures, and diffuse mineral deposits. Homografts with moderately elevated mineralization, well-preserved layered structure and sporadic infective changes proved to have the greatest durability. Homograft durability was also affected by the difference in host and donor age. CONCLUSION: Preimplantation factors affecting pathological changes determining homograft durability included morphological status of the graft itself and donor age; host-related factors included recipient age, endocarditis, native valve calcification, and host-donor matching (age difference between host and donor). A limited molecular mineralization may increase valvular durability, provided that no focal nodular calcifications exist that might adversely affect overall homograft integrity.

Adult↗
PubMed2003

[Relationship between carotid intima-media thickness, atherosclerosis risk factors and angiography findings in patients with coronary artery disease].

UNLABELLED: The aim was to determine relationship between carotid intima-media thickness and atherosclerosis risk factors and angiographic findings in patients with coronary artery disease. METHODS: We examined 172 consecutive patients, men and women, aged 58.5 +/- 9.35 years. Eligibility criteria included presence of coronary artery disease that was defined as a history of a heart attack or cardiac catheterization demonstrating > 50% stenosis of at least 1 coronary artery. B-mode ultrasound quantification of carotid artery intima-media thickness was obtained in all patients. Intima-media thickness was measured at left and right carotid arteries and expressed as the mean of the maxima in the common carotid artery, bifurcation and the internal carotid artery. Moreover, the mean of the maxima (IMT) was calculated at all sites. A grade of stenosis was identified and quantified by analyzing Doppler velocity spectrum in combination with measurement of stenosis area in all patients with severe lesions. Obtained results were compared with risk factors of atherosclerosis and angiographic findings on coronary artery angiograms. RESULTS: There was a statistically significant positive correlation between age (p = 0.0001), hypertension (p = 0.0001), hyperlipidaemia (p = 0.008), non-insulin-dependent-diabetes mellitus (p = 0.043) and intima-media thickness. In 157 (91.3%) patients intima-media thickening and plaques were present in carotid arteries. We observed high-grade stenosis of carotid arteries in 15 patients (8.7%) with coronary artery disease, furthermore all these patients have had at least two-vessel coronary artery disease. CONCLUSIONS: Alterations within carotid arteries: intia-media thickening and plagues were identified in 91.3% patients. We observed statistically significant correlation between IMT and advancing coronary artery disease. High-grade stenosis of carotid arteries was observed in 8.7% patients with coronary artery disease, furthermore in 13.7% patients with advanced coronary artery disease. IMT increases with age. Hypertension, hyperlipidemia and non-insulin-dependent diabetes mellitus are related to a greater IMT, whereas other risk factors didn't reveal that correlation.

Angioplasty, Balloon, Coronary↗
PubMed2002

Cardiorespiratory response to exercise in children after modified fontan operation.

OBJECTIVE: Examination of exercise function of Fontan patients and comparison with healthy control subjects. DESIGN: Fourteen patients (6 males, 8 females; age: 5.7-17 years, mean 8.1 years) after Fontan repair in New York Heart Association (NYHA) class I with rest O(2)sat > 85% requiring no cardiovascular medications performed graded exercises on a treadmill 0.5-3.2 years postoperatively (mean 1.8 years). During the tests the heart and respiratory rate, blood pressure, oxygen uptake, carbon dioxide production, minute ventilation, tidal volume and O(2)sat were recorded. Spirometry was performed before and during exercise. RESULTS: The peak VO(2)max in Fontan patients was significantly reduced compared with controls (p = 0.0002). Other parameters: anaerobic threshold (p = 0.0001); pulsO(2) (p = 0.00005); peak minute ventilation (p = 0.0014); physiological dead space to tidal volume ratio at peak exercise (p = 0.0004); maximal work rate (p = 0.00008); exercise time (p = 0.00003) were significantly reduced in univentricular patients. The heart rate at peak exercise was lower in the patients (p = 0.0003) and O(2)sat dropped significantly (p = 0.003). CONCLUSION: The aerobic capacity, work and ventilatory parameters in Fontan patients are markedly reduced compared with controls. The anaerobic threshold was significantly lower. The decreased O(2)sat at peak exercise may suggest intrapulmonary shunting.

Adolescent↗