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Konstantinos N Vemmos

Publications and source records attributed to Konstantinos N Vemmos.

13 recordsLinked to original sources
PubMed2006

Twenty-four-hour heart rate and blood pressure are additive markers of left ventricular mass in hypertensive subjects.

BACKGROUND: We investigated whether mean heart rate (HR(24)) and blood pressure (BP) parameters during 24-h ambulatory BP monitoring (ABP) are independent or additive markers of left ventricular (LV) mass in subjects with newly diagnosed, untreated hypertension. METHODS: A total of 250 patients (40% women, 60% men; mean age 59.6 +/- 11 years) with essential hypertension who were attending the outpatient Hypertension Unit were studied. All patients underwent 24-h ABP and HR monitoring as well as echocardiography for assessment of left ventricular (LV) dimensions and function. RESULTS: A decreasing HR24 or increasing ABP parameters (ie, systolic, diastolic, mean BP, and pulse pressure) were associated with increasing LV mass (P < .001) and wall thickness (P < .01). In multivariate analysis, after adjusting for age, gender, body surface area, body mass index, hematocrit, glucose, cholesterol, smoking, and each of the measured ABP parameters separately, decreasing HR24 was independently related to increasing LV mass in addition to ABP and body size parameters (P < .001). The addition of HR24 in different multivariate models for prediction of LV mass significantly increased the adjusted model r2 (range of r2 change: 0.039 to 0.064, P for change <.05). Decreasing HR24 or HR during daytime (6 am to 10 pm) was associated with a higher likelihood of LV hypertrophy in addition to ABP parameters (adjusted odds ratio 0.92 (CI 0.87 to 0.98), per 1 beat/min greater HR24 P = .002 and 0.93 (CI: 0.87 to 0.98), per 1 beat/min greater HR in the daytime P = .017). CONCLUSION: The 24-h HR and BP during ABP are independent and additive markers of increased LV mass in untreated hypertensive individuals.

Blood Pressure↗
PubMed2006

Primary prevention of arterial thromboembolism in the oldest old with atrial fibrillation--a randomized pilot trial comparing adjusted-dose and fixed low-dose coumadin with aspirin.

BACKGROUND: Anticoagulation therapy remains largely underused in older people with atrial fibrillation (AF). The aim of this pilot trial was to investigate the effects of low-intensity adjusted-dose and fixed-dose coumadin on the incidence of arterial thromboembolism and bleeding, as well as the efficacy of anticoagulation monitoring in elderly AF patients. METHODS: In this open-label, randomized trial we recruited patients over 75 years of age without previous stroke or systemic embolism. Patients were randomized into three groups, with group A receiving aspirin 100 mg/day, group B fixed-dose coumadin 1 mg/day; and group C adjusted-dose coumadin with a target range of international normalized ratios (INR) between 1.6 and 2.5. Primary endpoints (ischemic strokes and systemic embolisms) and secondary endpoints (deaths, myocardial infarctions, and major bleeding events) were prospectively documented. RESULTS: The study was discontinued 6 months after the enrollment of the first patient for safety reasons. During this period, 45 patients were recruited (15 patients in group A, 14 in group B, and 16 in group C). Over a mean follow-up period of 3.7 months (range: 1-6 months), two patients from group B developed a dangerous prolongation of the INR (7.0 and 4.2), which led to the discontinuation of fixed-dose coumadin. Another patient from the same group experienced a major bleeding event 1 month after enrollment in the study (INR: 5.5). The percentage of INR measurements within the target range was significantly (p<0.001) lower in group B (48.7%) than in group C (83.7%). CONCLUSIONS: Older people receiving fixed-dose oral anticoagulants may be at risk of developing a dangerous prolongation of their INR.

Journal Article↗
PubMed2005

Aetiopathogenesis and long-term outcome of isolated pontine infarcts.

BACKGROUND AND PURPOSE: Isolated pontine strokes cause characteristic neurological syndromes and have a good short-term prognosis. The aim of this study was to examine the long-term survival, cumulative recurrence rate and clinical handicap of patients with isolated pontine infarcts of different aetiology. METHODS: One hundred consecutive patients with an isolated pontine infarction were identified by imaging studies and evaluated prospectively. After extensive study, cases were classified according to the aetiopathogenetic mechanisms: stroke due to basilar artery branch disease (BABD), small-artery disease (SAD) and large-artery-occlusive disease (LAOD). During a mean follow-up period of 46 months, stroke presentation and initial course, early and long-term mortality, disability and recurrence were evaluated. RESULTS: BABD was the most frequent cause of isolated pontine ischaemia (43%), followed by SAD (34%) and LAOD (21%). Hypertension was the most prominent risk factor, especially among patients with SAD (94.1%). Neurological impairment on admission was more severe in the LAOD group, followed by BABD. After 1 month patients with LAOD had the highest cumulative mortality (14.3%, p = 0.026) and more severe disability (61.1%, p = 0.001). Five-year mortality rate was 20.6%, 14% and 23.8% in the SAD-, BABD- and in LAOD-group respectively (p = 0.776). Cumulative 5-year recurrence rate was 2.3 % for BABD, 14.3 % for LAOD, and 29.4 % for SAD (p = 0.011). CONCLUSIONS: Overall long-term survival of patients with isolated pontine infarcts is good. Initial differences regarding short-term outcome in infarctions of different aetiology resolve with time. Effective secondary prevention among SAD patients may limit stroke recurrence and positively influence long-term prognosis.

Aged↗
PubMed2005

Stroke etiology is associated with symptom onset during sleep.

BACKGROUND AND OBJECTIVES: Almost every fifth stroke occurs during sleep. Data about characteristics and etiology of stroke during sleep are conflicting. We investigated the association of the activity at stroke onset (onset during night sleep vs. onset while awake) with stroke subtypes of different etiology. METHODS: A total of 1448 patients with first-ever stroke with known time of symptom presentation were prospectively evaluated. Statistical comparisons were performed between patients with stroke during sleep and stroke while awake in terms of demographic features, known risk factors, vascular comorbidities, and stroke subtypes. Multiple variable logistic regression analyses were performed to identify predictor variables (including stroke risk factors and stroke subtypes) for stroke during sleep. RESULTS: Stroke during sleep was documented in 264 cases (18.2%). In subjects with stroke during sleep, lacunar infarction was the most prevalent stroke subtype (39%), while in patients with stroke while awake, small-vessel disease was the underlying mechanism significantly (P < .001) less often (13.8%). In contrast, patients with stroke while awake suffered significantly (P < .001) more frequently from intracerebral hemorrhage (18.2%) and cardioembolic stroke (34.9%) when compared with subjects with stroke during sleep (6.4% and 18.9%, respectively). The multiple variable logistic regression model identified the following factors as independent predictors of stroke during sleep: atrial fibrillation (odds ratio: 0.346, 95% confidence interval: 0.237-0.505, P < .001) and intracerebral hemorrhage versus ischemic stroke (odds ratio: 0.238, 95% confidence interval: 0.138-0.410, P < .001). Lacunar infarction was the only ischemic stroke subgroup that was positively associated with stroke during sleep (odds ratio: 2.568, 95% confidence interval: 1.447-4.560, P < .001). CONCLUSIONS: There are significant differences between stroke during sleep and stroke while awake concerning vascular risk profile and stroke etiologic subtypes.

Age Factors↗
PubMed2005

Association of blunted nocturnal blood pressure dip with intracerebral hemorrhage.

OBJECTIVES: Nondipping pattern of nocturnal blood pressure is associated with silent ischemic cerebrovascular lesions and lacunar infarctions. In this case-control study, we aimed to evaluate the association of diurnal blood pressure variation with the occurrence of intracerebral hemorrhage. METHODS: Ambulatory blood pressure monitoring was performed at 21-28 days after ictus in 78 first-ever unselective consecutive patients with intracerebral hemorrhage and in 80 age-adjusted and sex-adjusted controls who were referred to the hypertension center of our institution. The degree of nocturnal blood pressure dip was calculated as [(mean daytime values-mean night-time values)/mean daytime values]x100. Nondippers were defined as patients who exhibited a <10% nocturnal dip in systolic blood pressure. Logistic regression models were constructed to assess the association of nondipping status with intracerebral hemorrhage after adjusting for potential confounders (cardiovascular risk factors, office and ambulatory blood pressure levels). RESULTS: Prevalence of nondipping was significantly greater among cases than among controls (74.4% vs. 43.8%, P<0.001). Nondipping status was independently (P=0.033) associated with intracerebral hemorrhage (OR: 2.326, 95% CI: 1.068-5.050) in a multiple variable logistic regression model that adjusted for baseline characteristics, cardiovascular risk factors, office and ambulatory blood pressure variables. The magnitude of the nocturnal systolic blood pressure dipping was inversely related to the risk of intracerebral bleeding; the odds ratio for intracerebral hemorrhage associated with every 1% decrease in nocturnal systolic blood pressure dip was 1.143 (95% CI: 1.058-1.235, P=0.001). CONCLUSIONS: Given the previous reports that nondipping contributes to the risk of cerebral infarction, our results indicate that blunted nocturnal blood pressure dip may be also associated with the occurrence of intracerebral hemorrhage.

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PubMed2004

Pulse pressure in acute stroke is an independent predictor of long-term mortality.

The management of blood pressure (BP) during the acute phase of stroke remains a matter of debate. The aim of the present study was to evaluate a possible association between long-term mortality and BP values in acute stroke by means of BP monitoring. We studied a consecutive series of 198 first-ever acute stroke patients. BP monitoring was initiated in all subjects within 24 h of ictus. One year after stroke onset, 34 (17.7%) patients had died. Multivariate Cox regression analysis revealed only age, level of consciousness on admission, lacunar stroke and 24-hour pulse pressure (24-hour PP) as significant outcome predictors. The hazards ratio for 1-year mortality associated with every 10 mm Hg increase in 24 h PP was 1.39 (95% CI: 1.04-1.86, p = 0.028). The present results demonstrate that increasing 24-hour PP levels in patients with acute stroke are independently associated with higher long-term mortality. This may have implications in acute stroke BP management and warrants further investigation.

Aged↗
PubMed2004

Common carotid artery intima-media thickness in patients with brain infarction and intracerebral haemorrhage.

An increase in the intima-media thickness of the common carotid artery (CCA-IMT) is generally considered as an early marker of atherosclerosis and has been associated with a higher risk of stroke and myocardial infarction. There is no evidence of an association between the IMT and cerebral bleeding. We investigated cross-sectionally the diagnostic ability of vascular risk factors, including CCA-IMT, to distinguish between brain infarction (BI) and intracerebral haemorrhage (ICH). Patients suffering from BI (n = 126) had significantly (p < 0.05) higher CCA-IMT when compared to the ICH population (n = 30). The multinomial logistic regression procedure selected CCA-IMT as an independent factor able to discriminate between BI and ICH. The risk of BI versus ICH increased continuously with increasing CCA-IMT. After adjustment for cardiovascular risk factors the odds ratio for BI per 0.1 mm CCA-IMT increase was 1.29 (95% CI: 1.03-1.61). The present results demonstrate the possible predictive power of non-invasive measurement of the CCA-IMT with respect to BI versus ICH and deserve further investigation.

Aged↗
PubMed2004

Anticoagulation influences long-term outcome in patients with nonvalvular atrial fibrillation and severe ischemic stroke.

BACKGROUND: Limited data exist regarding long-term prognosis in patients with nonvalvular atrial fibrillation (AF) who have survived a severe, disabling stroke. OBJECTIVE: The aim of this study was to assess long-term prognosis and its determinants in a prospective case series of stroke survivors with AF and moderate to severe handicap. METHODS: From a consecutive series of AF patients with first-ever ischemic stroke, we evaluated prospectively those with moderate to severe disability (grade 4-5 on the modified Rankin Scale) who were treated during a 5-year follow-up period with either warfarin or aspirin. Death and recurrent vascular events were documented. RESULTS: Out of a pool of 438 AF patients, 191 were prospectively assessed. During a mean follow-up of 50.4 months, the cumulative 5-year mortality was 76.7% (95% CI, 69.0-84.3) and the 5-year recurrence rate was 33.7% (95% CI, 23.3-44.1). Cox regression analysis revealed that increasing age, increasing handicap, and aspirin versus warfarin were independent predictors of mortality. Prior transient ischemic attack and aspirin versus warfarin were predictors of vascular recurrence. Anticoagulation was associated with a decreased risk of death (hazard ratio [HR], 0.44; 95% CI, 0.27-0.70; P < 0.001) and recurrent thromboembolism (HR, 0.36; 95% CI, 0.17-0.77; P < 0.01). CONCLUSION: Our results suggest that chronic anticoagulation therapy may be effective in lengthening survival and preventing recurrent thromboembolism in AF patients who have suffered a severely disabling ischemic stroke.

Age Factors↗
PubMed2004

Progressive stroke due to essential thrombocythemia.

We report a case of progressive stroke, due to an intracranial thrombosis, leading to a high-grade stenosis of the internal carotid artery (ICA). Essential thrombocythemia (ET) was identified as the cause of thrombosis. Effective anticoagulation in the acute phase of cerebral ischemia prevented further thrombus organization and total vessel obstruction. After clinical improvement and normalization of platelet counts under hydroxyurea, anticoagulation was stopped and antiplatelet agents were subsequently administered.

Journal Article↗
PubMed2004

Blood pressure course in acute ischaemic stroke in relation to stroke subtype.

OBJECTIVES: Blood pressure (BP) management in acute stroke remains a matter of little consensus. Data on BP changes during the first hours of ictus are lacking. We aimed to evaluate the early spontaneous time course of BP in different ischaemic stroke (IS) subtypes. METHODS: Twenty-four h BP monitoring was performed in 200 first-ever hyper-acute IS patients. The recording was initiated and terminated at 3 h and 27 h of ictus respectively. All IS patients were classified on admission into the following subgroups of different etiology: large artery atherosclerotic stroke (LAA), cardio-embolic stroke (CE), lacunar stroke (LAC) and infarct of undetermined cause (IUC). Statistical comparisons between stroke subgroups were performed using one-way ANOVA and linear regression analyses were used to evaluate the influence of different factors in BP course. RESULTS: Although there were no significant differences in 24 h systolic (SBP) and diastolic (DBP) BP values between IS subgroups, a distinctly different SBP course was observed. The SBP dropped sharply in the LAA and LAC subgroups, while a more gradual decrease was monitored in the CE subgroup. Throughout the BP-recording, a SBP decrease of 10.1% (95% CI: 8.6-11.5) and 10.4% (95% CI: 9.0-11.8) was documented in patients with LAA and LAC respectively, while a milder drop was recorded in CE (3.7%, 95% CI: 2.4-5.0) and IUC (5.5%, 95% CI: 4.1-6.8). Increasing stroke severity (p<0.001) and brain oedema (p=0.013) was independently associated with a milder spontaneous SBP reduction. CONCLUSIONS: Spontaneous SBP course varies in acute ischaemic stroke subtypes of different etiology. This may have implications in the optimal management of post-stroke hypertension.

Acute Disease↗
PubMed2003

Association between 24-h blood pressure monitoring variables and brain oedema in patients with hyperacute stroke.

OBJECTIVE: To assess the effects of blood pressure (BP) values on oedema formation following hyperacute stroke. DESIGN: Prospective observational study. SETTING AND PATIENTS: Acute stroke-unit in University hospital. A total of 240 consecutive first-ever ischaemic or haemorrhagic stroke patients were recruited within 3 h of ictus. METHODS Casual and 24-h BP values were measured. Known stroke risk factors and clinical findings on admission were documented. Patients were imaged with computed tomography (CT) scan within 24 h from stroke onset and 5 days later in order to determine the presence of brain oedema. Patients who received antihypertensive medication during the BP monitoring were excluded. RESULTS: The main outcome measure was brain oedema formation, which was present in 78 (32.5%) patients. The 24-h systolic (SBP), diastolic (DBP) and mean BP values, 24-h pulse pressure and heart rate values were significantly higher in patients with brain oedema than in the reference group (stroke patients without brain swelling). On multiple variable analysis, containing clinical, demographic and BP monitoring variables, 24-h SBP remained significantly (P = 0.019) associated with brain oedema. The odds ratio for oedema formation associated with each 10-mmHg increase in 24 h SBP was 1.25 (95% confidence intervals: 1.04-1.51). During the first 27 h after onset SBP course showed a spontaneous decline in the reference group, which was not documented in patients with brain oedema. CONCLUSION: Elevated 24-h SBP values in the acute stroke period are associated with subsequent brain oedema formation.

Aged↗