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1.
J Postgrad Med ; 67(1): 43-45, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33533751

RESUMEN

Immune-checkpoint inhibitor mediated hepatobiliary injury is an emerging concern in cancer treatment. Most of these adverse reactions are attributed to nivolumab and are characterized by panlobular hepatitis. Large duct cholangiopathy related to these drugs is extremely rare. We present a case of adenocarcinoma of lung treated with pembrolizumab who developed biochemical and imaging features consistent with cholangiopathy characterized by common bile duct dilatation, wall enhancement, and gallbladder wall edema. On follow-up in the fourth month, the imaging features persisted despite the normalization of liver enzymes. To the best of our knowledge, this is the first description of diagnosis and follow-up imaging of pembrolizumab-related cholangiopathy in imaging literature.


Asunto(s)
Anticuerpos Monoclonales Humanizados/efectos adversos , Antineoplásicos Inmunológicos/efectos adversos , Enfermedad Hepática Crónica Inducida por Sustancias y Drogas , Enfermedades del Sistema Digestivo/patología , Adenocarcinoma del Pulmón/tratamiento farmacológico , Colangiografía , Conducto Colédoco , Enfermedades del Sistema Digestivo/inducido químicamente , Humanos , Neoplasias Pulmonares/tratamiento farmacológico
2.
Angiology ; 69(3): 249-255, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28367645

RESUMEN

AIM OF THE STUDY: We studied the clinical profile, management, and outcomes of patients with out-of-hospital cardiac arrest (OHCA) with and without ST-elevation myocardial infarction (STEMI). METHODS: Retrospective analysis of the 20-year registry data (January 1991- June 2010) was conducted on patients with cardiac disease hospitalized at Hamad General Hospital and Qatar Heart Hospital, Doha, Qatar. RESULTS: A total of 987 patients with OHCA were admitted to the cardiology department during the study period; among them, 296 (30%) patients had STEMI. Compared to the patients with OHCA without STEMI, the patients who had OHCA with STEMI were younger (53 ± 13 vs 58 ± 16 years; P = .001), more likely to be male (78% vs 34%; P = .001), smokers (35% vs 14%) but less likely to have hypertension (30% vs 48%; P = .001), diabetes (32% vs 47%, P = .001), and chronic renal failure (3.4% vs 9%; P = .002). The use of thrombolytic treatment in patients with STEMI increased from 21.6% (period 1991-1095) to 44.4% (period 2006-2010); P = .04. CONCLUSION: Percutaneous coronary intervention had increased significantly during the last quarter of the study. There was a decline in the in-hospital mortality among patients with STEMI during the last quarter of the study.


Asunto(s)
Hospitalización/estadística & datos numéricos , Paro Cardíaco Extrahospitalario/epidemiología , Paro Cardíaco Extrahospitalario/terapia , Sistema de Registros , Infarto del Miocardio con Elevación del ST/epidemiología , Infarto del Miocardio con Elevación del ST/terapia , Adulto , Anciano , Femenino , Fibrinolíticos/uso terapéutico , Mortalidad Hospitalaria , Humanos , Masculino , Persona de Mediana Edad , Paro Cardíaco Extrahospitalario/complicaciones , Evaluación de Procesos y Resultados en Atención de Salud , Intervención Coronaria Percutánea , Qatar , Estudios Retrospectivos , Infarto del Miocardio con Elevación del ST/complicaciones
3.
Angiology ; 66(8): 738-44, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25248442

RESUMEN

We analyzed the clinical presentation and outcomes (from 2003 to 2013) of heart failure (HF) with apparently normal systolic function (HFPEF). Based on the echocardiographic left ventricular ejection fraction (LVEF), patients were divided into 2 groups, group 1 (<50%) and group 2 (≥50%). Of 2212 patients with HF, 20% were in group 2. Patients in group 2 were more likely to be older, females, Arabs, hypertensive, and obese (P = .001). Patients in group 1 were mostly Asians and had more troponin-T positivity (P = .001). Inhospital cardiac arrest, shock, and deaths were significantly greater in group 1. On multivariate analysis, age, ST-segment elevation myocardial infarction, lack of on-admission ß-blockers, and angiotensin-converting enzyme inhibitors use were independent predictors of mortality. HFPEF is associated with less mortality compared to those who presented with reduced LVEF. On admission, use of evidence-based medications could in part predict this difference in the hospital outcome.


Asunto(s)
Insuficiencia Cardíaca/fisiopatología , Función Ventricular Izquierda , Factores de Edad , Anciano , Biomarcadores/sangre , Fármacos Cardiovasculares/uso terapéutico , Comorbilidad , Femenino , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/tratamiento farmacológico , Insuficiencia Cardíaca/etnología , Insuficiencia Cardíaca/mortalidad , Mortalidad Hospitalaria , Hospitalización , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Prevalencia , Pronóstico , Qatar/epidemiología , Grupos Raciales , Estudios Retrospectivos , Factores de Riesgo , Volumen Sistólico , Sístole , Factores de Tiempo , Troponina T/sangre
4.
Cardiol Res Pract ; 2014: 464323, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24868481

RESUMEN

We aimed to define the temporal trend in the initial Acute Myocardial Infarction (AMI) management and outcome during the last two decades in a Middle Eastern country. A total of 10,915 patients were admitted with initial AMI with mean age of 53 ± 11.8 years. Comparing the two decades (1991-2000) to (2001-2010), the use of antiplatelet drugs increased from 84% to 95%, ß -blockers increased from 38% to 56%, and angiotensin converting enzyme inhibitors (ACEI) increased from 12% to 36% (P < 0.001 for all). The rates of PCI increased from 2.5% to 14.6% and thrombolytic therapy decreased from 71% to 65% (P < 0.001 for all). While the rate of hospitalization with Initial MI increased from 34% to 66%, and the average length of hospital stay decreased from 6.4 ± 3 to 4.6 ± 3, all hospital outcomes parameters improved significantly including a 39% reduction in in-hospital Mortality. Multivariate logistic regression analysis showed that higher utilization of antiplatelet drugs, ß -blockers, and ACEI were the main contributors to better hospital outcomes. Over the study period, there was a significant increase in the hospitalization rate in patients presenting with initial AMI. Evidence-based medical therapies appear to be associated with a substantial improvement in outcome and in-hospital mortality.

5.
Angiology ; 64(1): 26-30, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22550348

RESUMEN

We assessed the prevalence of unrecognized diabetes mellitus (DM) in patients with acute coronary syndrome (ACS) as determined by elevated glycosylated hemoglobin (HbA1c), fasting plasma glucose (FPG), and random plasma glucose (RPG) levels. This prospective study recruited 583 patients admitted with ACS without previous diagnosis of DM during 1-year period. Glycosylated hemoglobin was checked for most patients especially those with high values of FPG and or RPG. Patients were classified according to their glycemic state into 123 (21.1%) with DM, 82 (14.1%) with prediabetes, and 57(9.8%) with stress hyperglycemia, while 321 (55%) were classified as nondiabetics. Glycosylated hemoglobin estimation in the setting of ACS was helpful in the diagnosis of DM to eliminate the effect of stress-induced hyperglycemia that might accompany this condition.


Asunto(s)
Síndrome Coronario Agudo/diagnóstico , Síndrome Coronario Agudo/epidemiología , Diabetes Mellitus/epidemiología , Hemoglobina Glucada , Hiperglucemia/epidemiología , Estado Prediabético/epidemiología , Glucemia , Femenino , Humanos , Masculino , Prevalencia , Estudios Prospectivos
6.
Angiology ; 64(3): 195-9, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22492251

RESUMEN

We evaluated the prevalence and clinical profile of patients with left main coronary artery disease (LMCA) in Qatar between 2006 and 2010. Patients were divided into 2 groups: patients with LMCA and patients without LMCA but had severe 3-vessel disease (VeD) eligible for surgical revascularization. Among 7000 patients who underwent coronary angiography, 210 patients had significant LMCA and 200 patients with severe 3VeD were matched for age and sex. Diabetes mellitus and hypertension were comparable in the 2 groups. Presentations with myocardial infarction or heart failure were comparable in both groups. Isolated LMCA was 4-fold higher in women (P = .02). Dyslipidemia and smoking were more prevalent in patients with distal and proximal lesions, respectively. Renal failure was independent predictor of LMCA (adjusted odds ratio: 2.6; 95% confidence interval: 1.43-4.69). One-year mortality was higher in LMCA (P = .01). The LMCA carries high mortality. Certain cardiovascular risk factors were important predictors of stenosis site.


Asunto(s)
Enfermedad de la Arteria Coronaria/epidemiología , Enfermedad de la Arteria Coronaria/diagnóstico , Dislipidemias/epidemiología , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Prevalencia , Qatar/epidemiología , Estudios Retrospectivos , Factores de Riesgo , Fumar/epidemiología
7.
J R Soc Promot Health ; 127(6): 265-7, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18085071

RESUMEN

BACKGROUND: The effects of shift work on coronary heart diseases (CHD) are well described. Most of the studies on coronary events in shift workers are supportive of the hypothesis that they are at increased risk. OBJECTIVE: The objective of this study was to investigate the relation shift work has to risk of CHD in a cohort of men from different Asian races working in a fertilizer plant in the Middle East. DESIGN: This is a case series of cohort study. SUBJECTS: The medical records for 2562 staff employed at the plant, from the start of the company in 1972 till 2003, were surveyed. Of these, 648 were shift workers and 1914 were daytime workers. A total of 223 employees had cardiovascular event. METHODS: For each case we recorded the date and age at start of employment, and the age at the time of diagnosis. Data from their last medical examination in the company were used to calculate their BMI, and to register whether they were smokers, had diabetes, or were senior or intermediate staff. Univariate and multivariate statistical analyses were performed. RESULTS: The incidence of CHD is significantly higher in shift workers (13.5%) compared with the daytime workers (7.1%). Also, there was a statistically significant difference between shift workers and daytime workers concerning hypertension and cerebrovascular incidents. CONCLUSION: Our results suggest the possibility of an overall relationship between shift work and cardiovascular diseases.


Asunto(s)
Enfermedad Coronaria/epidemiología , Industrias/estadística & datos numéricos , Admisión y Programación de Personal/estadística & datos numéricos , Tolerancia al Trabajo Programado/fisiología , Adulto , Estudios de Cohortes , Enfermedad Coronaria/etiología , Fertilizantes , Humanos , Masculino , Persona de Mediana Edad , Admisión y Programación de Personal/clasificación , Qatar/epidemiología , Medición de Riesgo
8.
J Postgrad Med ; 52(1): 30-3; discussion 33-4, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16534161

RESUMEN

BACKGROUND: Over one billion Muslims fast worldwide during the month of Ramadan. The impact of fasting on circadian presentation with acute cardiac events is unknown. AIM: To determine if fasting has any effect on the circadian presentation of acute cardiac events. SETTING AND DESIGN: A prospective study in a general hospital. MATERIALS AND METHODS: Patients with acute coronary events were divided into two groups based on the history of fasting. Information about age, gender, cardiovascular risk factor profiles and outcome was collected. The relationship of time of presentation of initial symptoms with fasting was evaluated using Student's t-test, Mann-Whitney U-test and chi2 analysis. RESULTS: Of the 1019 patients hospitalized during the study period, 162 were fasting. Although, fasting patients were more likely to present to the emergency department in the time periods 5-6 AM (10.5% vs 6.3%) and 11 PM (11.1% vs 7.1%) and were less likely to present in the time periods 1-2 PM (3.7% vs 7.2%) and 5-6 PM (3.7% vs 7.0%); these differences were not statistically significant. Fasting patients were less likely to have their symptoms start between 5 and 8 AM (11.1% vs 19.4%) and more likely to have symptoms between 5 and 6 PM (11.1% vs 6.0%) and 3 and 4 AM (11.1% vs 6.9%). These differences for time of initial symptoms were statistically significant (P=0.002). CONCLUSION: Exogenous factors associated with fasting, namely, the changes in food intake and/or sleep timings, affect the circadian rhythm and influence the timing of presentation of acute coronary events.


Asunto(s)
Angina Inestable/epidemiología , Ritmo Circadiano , Ayuno/efectos adversos , Insuficiencia Cardíaca/epidemiología , Infarto del Miocardio/epidemiología , Distribución de Chi-Cuadrado , Femenino , Hospitalización/estadística & datos numéricos , Humanos , Islamismo , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Qatar/epidemiología , Factores de Riesgo , Estadísticas no Paramétricas
9.
Blood Press ; 13(1): 41-6, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15083640

RESUMEN

AIMS: Cardiovascular disease is the leading cause of mortality and morbidity in the western world and has reached epidemic proportions. The incidence of congestive heart failure (CHD) and hypertension is also rising rapidly in many of the affluent Arab nations and cardiovascular diseases continue to be a leading cause of morbidity and mortality among adult Qataris and Asians residing in Qatar. OBJECTIVE: The objective of this study is to assess the effect of hypertension among patients admitted to hospital in Qatar with CHD and to identify risk factors that contribute to the development of CHD in hypertensive subjects. DESIGN: This is a retrospective cohort study. SETTING: Hamad General Hospital, Hamad Medical Corporation. SUBJECTS: All patients who were hospitalized with CHD with or without hypertension in the Hamad General Hospital, State of Qatar, from 1991 to 2001. METHODS: The diagnostic classification of definite CHD was made in accordance with criteria based on the International Classification of Disease, ninth revision (ICD-9]. RESULT: A total of 20,856 patients were treated during the 10-year period; 8446 were Qataris. Among them, 60% were males and 40% females. Among the total patients (3713) hospitalized with CHD, 1744 (46.9%) had hypertension. Furthermore, the incidence of hypertension was slightly higher in males than in females (56.4 vs 43.6%). A statistically significant difference was found between hypertensive and non-hypertensive cases with diabetes mellitus and angina. Hypertensive subjects were more likely to have diabetes (p < 0.001) and angina (p < 0.030). The mortality rate of CHD patients with hypertension was higher among Qataris than among non-Qataris (p < 0.038). CONCLUSION: Hypertension was the most common risk factor for CHD; it contributed a large proportion of heart failure cases in this population-based sample. Preventive strategies directed toward earlier detection of elevated blood pressure and its control are likely to offer the greatest promise for reducing the incidence of CHD and its associated mortality.


Asunto(s)
Insuficiencia Cardíaca/epidemiología , Hipertensión/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Antihipertensivos/uso terapéutico , Árabes , Asia/etnología , Estudios de Cohortes , Comorbilidad , Países en Desarrollo , Susceptibilidad a Enfermedades , Femenino , Insuficiencia Cardíaca/etnología , Insuficiencia Cardíaca/etiología , Insuficiencia Cardíaca/mortalidad , Insuficiencia Cardíaca/prevención & control , Insuficiencia Cardíaca/terapia , Humanos , Hipertensión/complicaciones , Hipertensión/etnología , Incidencia , Masculino , Persona de Mediana Edad , Pronóstico , Qatar/epidemiología , Estudios Retrospectivos , Cambio Social , Terapia Trombolítica
10.
J Cardiovasc Risk ; 8(1): 1-8, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11234721

RESUMEN

BACKGROUND: Why do some patients suffer acute myocardial infarction (MI) despite angiographically normal coronary arteries (NL + MI) whereas others enjoy an acute MI-free life despite extensive three-vessel disease (3VD-MI)? The present study contrasts these two groups to identify some differences in the risk profile. METHODS: In 10,000 patients admitted to the cardiology service, a first MI was confirmed in 2356 patients, of whom 1609 underwent coronary angiography. In 77 patients with MI, coronary angiography was found to be entirely normal (NL + MI, 77/1609, 4.1%). These were contrasted to 123 patients with severe three-vessel coronary disease but no MI (3VD-MI). RESULTS: Patients with NL + MI were 13 years younger (42 +/- 8.3 vs 55 +/- 10.5, P < 0.05), with 33 patients (43%) under the age 40 years, in contrast to only 9 patients (7.3%) in the 3VD group being this age. Patients with NC + MI were more often current smokers (80.5% vs 29% in the 3VD group; P < 0.01). Patients with 3VD-MI were, on the other hand, more often diabetic (54% vs 9% in the NL + MI group; P < 0.01) and had a higher cholesterol level (5.6 +/- 1.1 vs 4.9 +/- 1.0 Mmol/l, P < 0.01) as well as a higher incidence of chronic stable angina (52% vs 22%; P < 0.01) and heart failure (6% compared with 0% in the NL + MI group). Sixty-one out of 77 (79%) NL + MI patients had a single risk factor, and in 87%, this was smoking alone. Diabetes mellitus was rare and never occurred alone in this group. CONCLUSION: In patients who suffer MI despite normal coronary angiography, smoking is a major risk factor: In contrast, in patients with extensive coronary artery disease on angiography but no MI, diabetes rather than smoking is the dominant risk factor. The findings of this study support the view that the risk factors for stable and unstable coronary artery disease are different, as reflected by the contrast of the above groups at the extremes of the spectrum. Smoking appears to be a major risk factor for acute MI (even with normal coronary angiography), whereas diabetes is a major risk factor for more severe but more stable coronary artery disease.


Asunto(s)
Enfermedad Coronaria/epidemiología , Infarto del Miocardio/etiología , Fumar/efectos adversos , Adulto , Angiografía , Diabetes Mellitus/epidemiología , Femenino , Hemodinámica , Humanos , Hiperlipidemias/epidemiología , Hipertensión/epidemiología , Masculino , Persona de Mediana Edad , Análisis Multivariante , Infarto del Miocardio/epidemiología , Estudios Prospectivos , Análisis de Regresión , Factores de Riesgo , Fumar/epidemiología
12.
Biosystems ; 52(1-3): 197-216, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10636046

RESUMEN

In this paper we provide a model for micro-flow based bio-molecular computation (MF-BMC). It provides an abstraction for the design of algorithms which account for the constraints of the model. Our MF-BMC model uses abstractions of both the recombinant DNA (RDNA) technology as well as of the micro-flow technology and takes into account both of their limitations. For example, when considering the efficiency of the recombinant DNA operation of annealing, we take into account the limitation imposed by the concentration of the reactants. The fabrication technology used to construct MEMS is limited to constructing relatively thin 3D structures. We abstract this by limiting the model to a small constant number of layers (as is done with VLSI models). Besides our contribution of the MF-BMC model, the paper contains two other classes of results. The main result is the volume and time efficient algorithm for message routing in the MF-BMC model, specifically useful for PA-Match. We will show that routing of strands between chambers will occur in time O(N x D/ m x n), where N is the number of strands in the MF-BMC, n is the number of chambers where RDNA operations are occurring, D is the diameter of the topology of the layout of the chambers, and m is proportional to the channel width. Operations that need annealing, such as PA-Match, are shown feasible in O(N2logN/n/n) volume instead of the previous use of omega(N2) volume, with reasonable time constraints. Applications of the volume efficient algorithm include the use of the Join operation for databases, logarithmic depth solutions to SAT (Boolean formula satisfiability) problems and parallel algorithms that execute on a PRAM. Existent algorithms can be mapped to ones that work efficiently in the MF-BMC model, whereas previous methods for applications such as PRAM simulation in BMC were not both time and volume efficient. Our other class of results are theoretical lower bounds on the quantities of DNA and the time needed to solve a problem in the MF-BMC model, analogous to lower bounds in VLSI. We bound the product BT from below, and further show that BT2 has a stronger lower bound of I2. Here B is the maximum amount of information encoded in the MF-BMC system at a time. T is the time for an algorithm to complete, and I is the information content of a problem.


Asunto(s)
Biología Computacional/métodos , ADN/análisis , Modelos Moleculares , Animales , Simulación por Computador , ADN Recombinante/análisis , Humanos
13.
Cardiovasc Intervent Radiol ; 21(6): 481-6, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9853166

RESUMEN

PURPOSE: Thermal tissue damage (TTD) is customarily associated with some lasers. The thermal potential of rotational atherectomy (RA) devices is unknown. We investigated the temperature profile and potential TTD as well as the value of fluid flushing of an RA device. METHODS: We used a high-resolution infrared imaging system that can detect changes as small as 0.1 degree C to measure the temperature changes at the tip of a fast RA device with and without fluid flushing. To assess TTD, segments of porcine aorta were subjected to the rotating tip under controlled conditions, stained by a special histochemical stain (picrisirius red) and examined under normal and polarized light microscopy. RESULTS: There was significant heating of the rotating cam. The mean "peak" temperature rise was 52.8 +/- 16.9 degrees C. This was related to rotational speed; thus the "peak" temperature rise was 88.3 +/- 12.6 degrees C at 80,000 rpm and 17.3 +/- 3.8 degrees C at 20,000 rpm (p < 0.001, t-test). Fluid flushing at 18 ml/min reduced, but did not abolish, heating of the device (11.8 +/- 2.9 degrees C). A crater was observed in all segments exposed to the rotating tip. The following features were most notable: (i) A zone of "thermal" tissue damage extended radially from the crater reaching adventitia in some sections, especially at high speeds. This zone showed markedly reduced or absent birefringence. (ii) Fluid flushing of the catheter reduced the above changes but increased the incidence and extent of dissections in the media, especially when combined with high atherectomy speeds. (iii) These changes were observed in five of six specimens exposed to RA without flushing, but in only one of six with flushing (p < 0.05). (iv) None of the above changes was seen in control segments. CONCLUSION: RA is capable of generating significant heat and potential TTD. Fluid flushing reduced heating and TTD. These findings warrant further studies in vivo, and may influence the design of atherectomy devices.


Asunto(s)
Aorta/cirugía , Aterectomía/efectos adversos , Aterectomía/instrumentación , Electrocoagulación/efectos adversos , Análisis de Varianza , Animales , Aorta/patología , Distribución de Chi-Cuadrado , Técnicas de Cultivo , Seguridad de Equipos , Modelos Cardiovasculares , Valores de Referencia , Instrumentos Quirúrgicos/efectos adversos , Porcinos , Termografía
14.
Angiology ; 49(10): 833-42, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9783648

RESUMEN

The interaction of atherectomy devices with the arterial wall is the focus of many studies, but their effect on the surrounding blood is largely unknown. This is a detailed investigation on the effects of a rotational atherectomy device with a fast rotating tip on platelet structure and function. Platelet-rich plasma (PRP) was obtained from six volunteers, divided into 5 mL samples, and subjected to the atherectomy tip rotating at 20, 40, or 80 thousand rpm for 30 or 60 seconds. Platelet aggregation to collagen or adenosine diphosphate (ADP) was obtained in all samples by means of a dual-chamber optical aggregometer. The fast rotating catheter tip caused marked inhibition of platelet aggregation to both collagen and ADP. The maximum extent of aggregation was reduced from 85% +/-2.8 in control to 46% +/-4.8 with collagen (p<0.01) and from 86.1% +/-6.9 to 25.1% +/-4.3 with ADP (p<0.01). The rate of aggregation (measured at 4 minutes) dropped from 81.3% +/-2.7 to 40% +/-4.5 and from 73.9% +/-8.5 to 12.5% +/-2.6 (p<0.005) with collagen and ADP, respectively. These effects were related to rotating speed and duration of exposure. ATP release in response to collagen fell from 2.63 +/-0.13 nMol in control to 0.7 +/-0.1 nMol, p<0.001 after exposure to the rotating tip. There was no significant change in platelet count, nor was there formation of platelet aggregates (platelet aggregate ratio remained unchanged) to account for these phenomena. Furthermore, transmission electron microscopy showed no significant platelet disruption or release of granules, and little signs of activation were seen even after addition of collagen. This is the first study to demonstrate that exposure to a fast rotating catheter tip inhibits in vitro platelet aggregation and ATP release. There were no apparent loss of integrity of platelet structure, release of granules, or formation of platelet aggregates. This phenomenon and its clinical implication justify further investigation.


Asunto(s)
Adenosina Trifosfato/metabolismo , Aterectomía Coronaria/instrumentación , Agregación Plaquetaria , Colágeno/farmacología , Humanos , Plasma , Recuento de Plaquetas
15.
Angiology ; 49(8): 625-30, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9717892

RESUMEN

Cardiac catheterization in Qatar was initiated in July 1982. In ten years, a total of 3900 procedures were performed at Hamad General Hospital. Computerized data registry has been maintained since 1982. Isolated coronary angiography was done in 2911 patients; of these, 2635 (90.5%) were men, and 276 (9.5%) were women, the average age of the patients was 47+/-9.2 years (range, twenty-five to eighty-eight). Patients' nationality was Qatari in 492 (17%), and other Arabs in 610 (21%), and 1512 (52%) were from the Asian subcontinent. Myocardial infarction was the most common indication (43%). Single-vessel disease was found in 638 (22%), two-vessel disease in 630 (22%), three-vessel disease in 950 (33%), and nonsignificant coronary artery disease in 693 (24%) patients. Morbidity related to the coronary angiography was reported in 147 (5%) patients, but there was no mortality related to the procedure. In 822 (28%) patients, the age was forty years or younger. The angiographic findings of these younger patients were compared with those of the older ones. Younger patients were usually men of Asian subcontinental origin with a recent myocardial infarction (MI). Often, they had normal coronary arteries or single-vessel disease. Patients of Asian subcontinent origin were usually young male patients with a recent MI, who receive streptokinase, and have single-vessel disease.


Asunto(s)
Angiografía Coronaria/estadística & datos numéricos , Enfermedad Coronaria/epidemiología , Adulto , Cateterismo Cardíaco/efectos adversos , Cateterismo Cardíaco/estadística & datos numéricos , Angiografía Coronaria/efectos adversos , Enfermedad Coronaria/diagnóstico por imagen , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Qatar/epidemiología , Sistema de Registros/estadística & datos numéricos
16.
Eur J Vasc Surg ; 8(4): 494-501, 1994 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8088403

RESUMEN

A conventional continuous wave Nd-YAG medical laser system delivered by transparent sapphire tipped optical fibres was used for percutaneous recanalisation of 32 chronic femoropopliteal occlusions in 27 patients (19 men, eight women; median age 68 years, range 46-83 years). Twenty-four patients had severe intermittent claudication and three had critical ischaemia. The median occlusion length was 8 cm (range 3-35 cm) and lesions were not negotiable by guidewire. Laser energy was delivered at powers of 10-15 Watts using intermittent 1 second emissions (mean total energy 315 Joules, range 30-1015]). The sapphire tips used were 1.8 to 3.0 mm diameter. After laser recanalisation adjunctive balloon dilatation was necessary to widen the resulting lumen. All patients received anti-platelet therapy. Initial clinical success was achieved in 22 limbs (69%) with symptomatic relief and increase in mean (+/- S.D.) ankle-brachial pressure ratio from 0.52 (+/- 0.25) to 0.80 (+/- 0.21) [Mann-Whitney U, p < 0.001]. Recanalisation was unsuccessful in all calcified lesions (four cases). There was a high incidence of vessel perforation (28%) and wall dissection (25%). Emergency surgery was not required after failed procedures. The median follow-up was 12 months (range 6-20 months). By 6 months, 15 of 22 successfully recanalised lesions (68%) had reoccluded. The cumulative primary patency at 1 year was only 12%. These disappointing results do not support routine use of this system. Clearly, modifications of the laser/delivery system or the technique, or both, are required. The aim should be to achieve sole laser recanalisation without concomitant balloon dilatation.


Asunto(s)
Angioplastia de Balón Asistida por Láser/instrumentación , Arteriopatías Oclusivas/cirugía , Arteria Femoral/cirugía , Arteria Poplítea/cirugía , Anciano , Angioplastia de Balón Asistida por Láser/métodos , Arteriopatías Oclusivas/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Estudios Prospectivos , Recurrencia , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
17.
Eur J Nucl Med ; 19(1): 6-13, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1532146

RESUMEN

In a prospective study, a radionuclide technique was used to evaluate the limb blood flow (LBF) changes in 30 patients undergoing dynamic (n = 15) or balloon (n = 15) angioplasty for arterial occlusions or stenoses, respectively. The results were compared with Doppler Ankle Brachial Index (DABI) and treadmill exercise tests. Whilst LBF values (ml of blood flow per 100 ml of limb volume per min) were significantly lower in limbs with arterial occlusion than stenosis (4.5 +/- 0.46 and 6.4 +/- 0.74, respectively; P less than 0.05). DABI provided no discrimination. Immediately after balloon angioplasty, there was a fall in DABI, from 0.60 +/- 0.05 to 0.47 +/- 0.04 (P less than 0.05), which rose 24 h later to 0.73 +/- 0.02 (P less than 0.01). Following dynamic angioplasty, DABI improved from 0.60 +/- 0.05 to 0.66 +/- 0.02 (P less than 0.05). At 3 weeks, the LBF improved from 4.6 +/- 0.66 to 11.1 +/- 0.53 (P less than 0.001) following dynamic angioplasty and from 6.2 +/- 0.68 to 8.53 +/- 0.81 (P less than 0.001) following balloon angioplasty. "Normal" LBF (greater than 10 ml/100 ml per min) was achieved in 80% of patients who underwent successful dynamic angioplasty but in only 36% of the balloon group (P less than 0.05, chi 2-test). Reproducibility of repeated LBF measurements in control limbs was superior to that of DABI. This was indicated by a lower coefficient of variation, 13.8% compared with 25.2%, and a higher correlation coefficient, r = 0.79 compared with 0.27. Treadmill exercise tests were invalid or impossible in 30% of all occasions.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Angioplastia de Balón , Arteriopatías Oclusivas/terapia , Velocidad del Flujo Sanguíneo , Extremidades/irrigación sanguínea , Arteriopatías Oclusivas/diagnóstico por imagen , Arteriopatías Oclusivas/epidemiología , Estudios de Evaluación como Asunto , Prueba de Esfuerzo , Extremidades/diagnóstico por imagen , Femenino , Humanos , Masculino , Estudios Prospectivos , Cintigrafía , Ultrasonografía
18.
Cardiovasc Intervent Radiol ; 14(4): 222-7; discussion 227-9, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1913736

RESUMEN

Angioscopy was used to evaluate the "self-centering" ability of three Kensey catheters (KC) with different flexibility: one 8Fr "peripheral" and two 5Fr "coronary" (I & II). Angioscopic observations were made inside arteries, 5-18 mm in diameter. There was a good correlation between flexibility and self-centering of the KC [r = 0.83, p less than 0.05]. Increasing the flow rate of rinsing solution from 18 to 60 ml/min prolonged coaxial position from 8.9 +/- 3.3 to 36 +/- 2.2 sec/min of activation [p less than 0.001]. A smaller effect on coaxial position was exerted by increasing cam speed from 5.2 +/- 0.7 to 19.2 +/- 1.6 sec/min (p less than 0.001). In conclusion, angioscopy showed that the KC has a limited ability to maintain a coaxial position inside the arterial lumen and operators cannot rely on its self-centering property.


Asunto(s)
Angioplastia Coronaria con Balón/instrumentación , Cateterismo Periférico , Angioplastia Coronaria con Balón/métodos , Animales , Perros , Endoscopía , Técnicas In Vitro , Porcinos
19.
J Biomed Eng ; 13(3): 221-4, 1991 May.
Artículo en Inglés | MEDLINE | ID: mdl-1870333

RESUMEN

A technique of isotope limb blood flow (ILBF) measurement employing Technetium-labelled human albumin and a gamma camera, was used to assess limb perfusion in 19 patients undergoing percutaneous laser angioplasty, both before and one month after treatment. Twenty-three limbs with femoro-popliteal occlusions ranging in length from 3-35 cm (median 8 cm) were recanalized using an Nd-YAG laser and sapphire tipped optical fibre. Primary angiographic success was achieved in 19 lesions of which 6 re-occluded within the first month, and 13 remained patent with relief of symptoms. Clinically successful procedures were associated with a large increase in ILBF. However, normal blood flow was restored in only 54% of limbs. There was a slight decrease in limb perfusion after failed laser angioplasty but this was not statistically significant in this small series. Furthermore, there was no clinically apparent circulatory compromise, or need for urgent surgical bypass in failed cases. We conclude that ILBF is a useful means of assessing patients undergoing laser angioplasty, particularly for detecting small flow changes in patients who are unable to complete a standard exercise test. Its use can be recommended for assessing blood flow changes following other forms of limb revascularization.


Asunto(s)
Angioplastia por Láser , Arteriopatías Oclusivas/cirugía , Arteria Femoral , Pierna/irrigación sanguínea , Arteria Poplítea , Agregado de Albúmina Marcado con Tecnecio Tc 99m , Anciano , Angioplastia por Láser/efectos adversos , Arteriopatías Oclusivas/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia , Flujo Sanguíneo Regional , Reproducibilidad de los Resultados
20.
Angiology ; 41(10): 809-16, 1990 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2145785

RESUMEN

The authors have used ultrathin angioscopes with high optical resolution to assess the effects of dynamic angioplasty in vitro and in vivo. Experimentally, angioscopy was used to study the effects of the 5F "Kensey" catheter in "normal" porcine coronary arteries (NPCA) and postmortem human coronary arteries (PMHCA). In NPCA, the catheter keeps a coaxial position. Intimal flaps (IFs) were seen in 21/23 NPCAs. They occurred with all cam rotation speeds and were usually single and small (less than 25% of lumen). Perforations in patent arteries were rare (1/23). However, when the catheter was forced against the wall by passing through a narrowing of 5F diameter (made by a band ligature), perforations were more common at higher cam speeds. The epicardium remained intact in two thirds of perforations. Angioscopy visualized perforations in only 10% of cases (1/10), the common sign being that of large and multiple intimal flaps, which were often obstructive (5/10). In PMHCAs, angioscopy was more sensitive than angiography in detecting atheromatous lesions. The authors were able to give a better assessment of the effect of dynamic angioplasty on treated lesions, including the demonstration of intimal flaps that were not visible on angiography. In vivo, they have performed percutaneous angioscopy before and after dynamic angioplasty using 8 French Kensey catheters. Angioscopy revealed features that were not shown angiographically.


Asunto(s)
Angioplastia de Balón/efectos adversos , Arteriopatías Oclusivas/terapia , Vasos Coronarios , Arteria Femoral , Arteria Ilíaca , Animales , Arteriopatías Oclusivas/diagnóstico , Autopsia , Vasos Coronarios/lesiones , Humanos , Porcinos
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