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Featured researches published by Fons Kessels.


Heart | 1997

Cardiac valve calcification: characteristics of patients with calcification of the mitral annulus or aortic valve

Arthur Boon; Emile C. Cheriex; Jan Lodder; Fons Kessels

Aims To determine whether mitral annular calcification and aortic valve calcification, with or without stenosis, are expressions of atherosclerotic disease. Methods The incidence of atherosclerotic risk factors was analysed in patients with mitral annular calcification and aortic valve calcification and in control patients from a prospective echocardiographic database of 8160 consecutive patients; 657 patients (8%) were identified with mitral annular calcification and 815 (9%) with a calcified aortic valve, of whom 515 (6.3%) had stenosis with a minimal aortic valve gradient of 16 mm Hg. In these patients, cardiac and vascular risk factors were compared with 568 control patients using multiple logistic regression analysis. Results Age (odds ratio (OR) varying from 5.78 to 104, depending on age class), female sex (OR 1.75), hypertension (OR 2.38), diabetes mellitus (OR 2.85), and hypercholesterolaemia (OR 2.95) were strongly and significantly associated with aortic valve calcification without stenosis, as were age (OR varying from 8.82 to 67, depending on age class), female sex (OR 2.22), hypertension (OR 2.72), diabetes mellitus (OR 2.49), and hypercholesterolaemia (OR 2.86) with mitral annular calcification. Age (OR varying from 1.11 to 7.7), hypertension (OR 1.91), and hypercholesterolaemia (OR 2.55) were strongly and significantly associated with stenotic aortic valve calcification. Conclusions Mitral annular calcification and stenotic or non-stenotic aortic valve calcification have a high incidence of atherosclerotic risk factors, suggesting they should be considered as manifestations of generalised atherosclerosis.


Annals of Surgery | 2007

Somatic and psychologic predictors of long-term unfavorable outcome after surgical intervention

Madelon L. Peters; Micha Sommer; Janneke M. de Rijke; Fons Kessels; Erik Heineman; Jacob Patijn; Marco A.E. Marcus; Johan W.S. Vlaeyen; Maarten van Kleef

Objective:To identify somatic and psychologic predictors of pain, functional limitations, global perceived recovery, and quality of life 6 months after surgical intervention. Summary Background Data:Recent studies have indicated that chronic pain after surgical intervention is more common than previously assumed. Several demographic and somatic predictors of long-term unfavorable outcome have been identified, but little is known about the contribution of psychologic risk factors. Methods:A prospective cohort study, including 625 patients undergoing elective surgery at the University Hospital Maastricht, The Netherlands, was conducted between February and August 2003. Psychologic questionnaires were completed preoperatively and acute postoperative pain was recorded until 4 days after the operation. Six months later, all patients received follow-up questionnaires to assess pain, functional limitations, global perceived recovery, and quality of life. Multivariable logistic regression analyses were used to estimate relative risk of poor outcome in terms of pain, functional limitations, and global recovery. Multivariable linear regression analysis was used to assess associations with quality of life at 6 months. Results:The most important somatic predictors of unfavorable outcome were duration of the operation and high levels of acute postoperative pain. Patients reporting high levels of pain 4 days after the operation and patients undergoing an operation of longer than 3 hours were at risk for increased pain, increased functional limitations, poor global recovery, and reported lower levels of quality of life 6 months after the operation. Psychologic variables that influenced long-term outcome were preoperative fear of surgery and optimism. Fear of the long-term consequences of the operation was associated with more pain, poor global recovery, and worse quality of life 6 months later, whereas optimism was associated with better recovery and higher quality of life. Conclusions:This study was the first to identify the joint contribution of somatic and psychologic factors to chronic pain, functional limitations, and quality of life 6 months after surgical interventions. It replicates previous findings that intense acute postoperative pain is a risk factor for long-term adverse outcome and also identified additional risk factors, namely, long duration of the operation, ASA status, and preoperative fear of surgery.


Journal of Clinical Epidemiology | 2003

Stroke subtype and mortality. a follow-up study in 998 patients with a first cerebral infarct.

Gosse de Jong; Lisette van Raak; Fons Kessels; Jan Lodder

The aim of this article was to study mortality following a first-ever cerebral infarct, accounting for ischemic stroke subtypes (lacunar, cardioembolic, atherothrombotic) and relevant prognostic variables. This study was done from s a hospital-based prospective registry of all patients with a first cerebral infarct, with a high case ascertainment of first and recurrent stroke by CT. We used a cross-sectional follow-up, using standardized methods. Analyses were performed using crude comparison of mortality data and death causes between stroke subtypes. We analyzed 30-day case fatality and 1-year mortality in 30-day survivors by means of logistic regression analysis, and mortality in 1-year survivors by means of Cox proportional hazard modeling. We also constructed Kaplan-Meier survival curves, and used log-rank testing for differences between stroke subtypes. Thirty-day case fatality was 10%, 1-year mortality 15%, and after 1-year mortality 16%. Mean follow-up was 691, SD 521 days. At the end of follow-up 36% of all patients had died. Mortality was at all three time points lowest in lacunar stroke (2, 12, and 14%, respectively), intermediate in atherothrombotic stroke (10, 16, and 15%, respectively), and highest in cardioembolic stroke (23, 22, and 21%, respectively). Death related to recurrent stroke was similar in all three stroke subtypes (13-16%). Although 30-day case fatality rate was low in lacunar stroke, a quarter of lacunar stroke patients had died at the end of follow-up. Diabetes mellitus, age, stroke subtype, and initial stroke severity were independent predictors of 30-day case fatality, but only diabetes and age were consistent independent predictors for later mortality. Recurrent stroke and heart failure were important death causes. Prognosis for (future) death following a first cerebral infarct differs between stroke subtypes; lacunar stroke patients have the lowest mortality. However, lacunar stroke cannot be regarded as a mild stroke type, as after 2 years more than a quarter of such stroke patients had died. Cardioembolic stroke patients have the grimmest prognosis: more than half of them had died within 1.5 years. Better prognosis for long-term survival following stroke may be achieved by therapies which lower the risk of stroke recurrence, provide better treatment of heart failure, or both.


Stroke | 1994

Silent brain infarcts in 755 consecutive patients with a first-ever supratentorial ischemic stroke. Relationship with index-stroke subtype, vascular risk factors, and mortality.

A Boon; J. Lodder; L Heuts-van Raak; Fons Kessels

We wanted to establish independent associations of various clinical variables, computed tomographic (CT) scan features, presenting stroke subtypes, and outcome with the presence of silent infarcts on CT. Methods We studied 755 consecutive patients in a prospective registration of patients with first-ever supratentorial atherothrombotic, cardioembolic, or lacunar stroke or stroke of undetermined cause by multiple logistic regression analysis. Results Two hundred six patients (27%) with a first symptomatic territorial or small deep ischemic stroke had one or more silent infarcts on CT. Of all silent lesions, 169 (82%) were small and deep. Silent infarcts were significantly more strongly associated with a lacunar than atherothrombotic (odds ratio [OR], 1.59; 95% confidence interval [CI], 1.02 to 2.47; P=.039) or cardioembolic (OR, 1.89; 95% CI, 1.2 to 2.99; P=.005) index stroke. Silent territorial lesions were more strongly associated with cardioembolic than with lacunar stroke but not with atherothrombotic stroke. In this respect, no differences were found between the atherothrombotic and undetermined-cause group. Advanced age and hypertension were the only risk factors that were significantly associated with silent infarcts (OR, 1.76; 95% CI, 1.14 to 2.71; P=.0U; and OR, 1.58; 95% CI, 1.13 to 2.21; P=.001; respectively), mainly because of a strong independent association of these risk factors with silent small deep infarcts (OR, 1.75; 95% CI, 1.10 to 2.79; P=.018; and OR, 1.57; 95% CI, 1.09 to 2.24; P=.014; respectively). A cardioembolic source or atrial fibrillation in specific was not independently associated with any type or number of silent infarcts. Significant carotid stenosis (diameter reduction >50%) was not significantly associated with any type of silent lesion. Initial severe handicap (Rankin Scale score >3), 30-day case fatality rate, and 1-year mortality were not affected by the presence of silent infarcts. Conclusions The strong association of silent small deep lesions with first symptomatic small deep infarcts suggests a common underlying mechanism (presumably small-vessel vasculopathy), whereas cardiogenic embolism and large-vessel thromboembolism are the most likely causes in both silent and first symptomatic territorial infarcts. Single or multiple silent infarcts do not predict a cardioembolic stroke mechanism in first symptomatic supratentorial brain infarcts. As silent infarcts do not predict the cause of carotid embolic stroke in first symptomatic brain infarcts, their presence should not influence the decision on carotid surgery. Silent infarcts do not affect the degree of initial handicap, 30-day case fatality, or 1-year mortality. The significance of silent infarcts for predicting possible future cognitive decline and risk of recurrent stroke deserves further study.


Cerebrovascular Diseases | 2009

Endothelial dysfunction in lacunar stroke: a systematic review.

Iris L.H. Knottnerus; Hugo ten Cate; Jan Lodder; Fons Kessels; Robert J. van Oostenbrugge

Background: Endothelial dysfunction is thought to play an important role in the pathogenesis and progression of cerebral small-vessel disease in lacunar stroke patients. Methods: We systematically searched the literature (MEDLINE, EMBASE) for evidence of endothelial activation and dysfunction in lacunar stroke. The selected papers were assessed by a predefined checklist to estimate methodological and informative quality. The papers were categorized into subheadings concerning the different physiologic functions of the endothelium and a subheading concerning toxins for the endothelium. Results: 29 articles were eligible for further analysis. We found 16 publications on regulation of vascular tone by the endothelium, which showed an impaired function at several time points after the stroke by means of different clinical methods (e.g. flow-mediated vasodilatation and CO2 reactivity). Nine references showed elevated levels of markers of hemostatic function of the vascular endothelium (e.g. von Willebrand factor, thrombomodulin) in acute and subsequent phases. In 4 papers, adhesion molecules (e.g. E- and P-selectin) were elevated only during the acute phase. Homocysteine, a toxin for the endothelium, was elevated in patients in 3 papers. Conclusions: The current literature suggests that endothelial dysfunction might be involved in the pathogenesis of lacunar stroke, especially in those patients with concomitant silent lacunar infarcts and ischemic white matter lesions. Future research on endothelial function in lacunar stroke should concentrate on long-term clinical as well as radiological follow-up in well-defined cases and combine multiple methods to evaluate endothelial function.


Neuromodulation | 2003

Percutaneous pulsed radiofrequency treatment of the cervical dorsal root ganglion in the treatment of chronic cervical pain syndromes: a clinical audit.

J. Van Zundert; I.E. Lame; A. de Louw; Jacobus F.A. Jansen; Fons Kessels; Jacob Patijn; M. van Kleef

Cervicogenic headache and cervicobrachialgia are frequent diagnoses of chronic cervical pain. After failure of conservative treatment, an interventional approach may be indicated in the absence of any indication for causal surgical treatment. The pulsed radiofrequency (PRF) technique exposes the nerve to a high‐frequency electric field while the temperature of the electrode tip does not exceed 42°C. This method is thought to be nondestructive and almost free of neurologic side effects and complications. Our extended pilot study was performed to confirm the perceived efficacy of PRF for short‐ and long‐term relief of chronic cervical pain. We carried out a clinical audit of the first 18 patients treated with PRF at the cervical dorsal root ganglion. An independent evaluator reviewed the medical records. Patients with good clinical results at 8 weeks were evaluated for long‐term effect (> 6 months), based on a 7‐point Likert scale. Thirteen patients (72%) showed short‐term clinical success (≥ 50% pain relief). Mean follow‐up was 19.4 months (SD 8.9 months), maximum 2.5 years. The duration of satisfactory pain relief (6 or 7 on the Likert scale) varied between 2 and over 30 months, with a mean duration of 9.2 months (SD 11.2 months). Kaplan‐Meier analysis illustrated that 50% of patients experienced success 3 months after treatment. We could not identify predictive variables for clinical outcome. None of the patients reported post‐treatment neuritis or other adverse events. To our knowledge, this is the first documented series of chronic cervical pain syndromes treated with PRF. Satisfactory pain relief of at least 50% was achieved in 13 of 18 (72%) patients at 8 weeks. More than one year after treatment, six patients (33%) continue to rate treatment outcome as good or very good. No side effects were reported. j


Stroke | 1996

Risk of Stroke in a Cohort of 815 Patients With Calcification of the Aortic Valve With or Without Stenosis

Arthur Boon; Jan Lodder; Emile Cheriex; Fons Kessels

BACKGROUND AND PURPOSE We sought to establish the possible role of calcification of the aortic valve with or without stenosis as a risk factor for stroke. METHODS Occurrences of stroke, stroke subtypes, and concomitant cardiovascular risk factors were prospectively analyzed in 300 patients with echocardiographic evidence of aortic valve calcification, 515 patients with calcified aortic valve stenosis, and 562 control subjects. RESULTS Twenty-four patients with aortic valve calcification, 24 patients with calcified aortic valve stenosis, and 27 control subjects had a stroke during follow-up. Using Cox proportional hazards models, we found that strokes were not significantly associated with aortic valve calcification with or without stenosis, but hypertension and any carotid stenosis were associated. On multiple logistic regression analysis, we did not find any association between one of the two valve lesions and indirect possible indications of cardiogenic embolism such as territorial as opposed to small deep brain infarcts or the presence of silent brain infarcts. CONCLUSIONS Aortic valve calcification with or without stenosis is not a risk factor for stroke.


Seizure-european Journal of Epilepsy | 1996

Late seizures following a first symptomatic brain infarct are related to large infarcts involving the posterior area around the lateral sulcus

Lisette Heuts-van Raak; Jan Lodder; Fons Kessels

Controversies exist concerning factors that contribute to the occurrence of epileptic seizures after stroke. Therefore, we studied prospectively the occurrence of seizures in 322 patients with a first-ever CT-confirmed symptomatic territorial brain infarct involving the cortex. We also studied potential risk factors for seizures, and gave special attention to cortical infarct location. Fifty-four patients developed post-stroke seizures. We distinguished between early- and late-onset seizures, occurring within two weeks following stroke-onset, or later than two weeks, respectively. We found that patients of 65 years or older with a cardioembolic brain infarct involving the middle temporal or post-central gyrus, had an almost eight times increased risk of early-onset seizures, whereas patients with a large brain infarct involving the supramarginal or superior temporal gyrus, had a five times increased risk of late-onset seizures. We conclude that risk factors and epileptogenic cortical areas for post brain infarct seizures can be identified, which however, differ between early- and late-onset seizures. These two seizure types may also differ in terms of seizure mechanism. Our findings may influence the decision on prophylactic treatment with antiepileptic drugs in stroke patients.


Cerebrovascular Diseases | 1998

Neuroprotection as Initial Therapy in Acute Stroke

Carlos Cantú; Jorge Villarreal; Jose Luis Soto; Fernando Barinagarrementeria; Benedikt G.H. Schoser; Veit U. Becker; Bernd Eckert; Hermann Zeumer; Andreas Thie; Lausanne J. Bogousslavsky; Mannheim M. Hennerici; M. Schmal; Carmine Marini; Antonio Carolei; M. Di Napoli; Fons Kessels; J. Lodder; Michael Eliasziw; J. David Spence; Henry J. M. Barnett; Dean M. Wingerchuk; Eelco F. M. Wijdicks; Jimmy R. Fulgham; Wouter I. Schievink; Jerry A. Katzmann; David G. Piepgras; G. Alistair Lammie; Joanna M. Wardlaw; Martin Dennis; J. Donald Easton

Although a considerable body of scientific data is now available on neuroprotection in acute ischaemic stroke, this field is not yet established in clinical practice. At its third meeting, the European Ad Hoc Consensus Group considered the potential for neuroprotection in acute stroke and the practical problems attendant on the existence of a very limited therapeutic window before irreversible brain damage occurs, and came to the following conclusions. Neuroprotectants in Clinical Development: Convincing clinical evidence for an efficacious neuroprotective treatment in acute stroke is still required. Caution should be exercised in interpreting and extrapolating experimental results to stroke patients, who are a very heterogeneous group. The limitations of the time windows and the outcome measures chosen in trials of acute stroke therapy have an important influence on the results. The overall distribution of functional outcomes provides more statistical information than the proportion above a threshold outcome value. Neurological outcome should also be assessed. Neuroprotectants should not be tested clinically in phase II or phase III trials in a time window that exceeds those determined in experimental studies. The harmful effects of a drug in humans may override its neuroprotective potential determined in animals. Agents that act at several different levels in the ischaemic cascade may be more effective than those with a single mechanism of action. Current In-Hospital Management of Acute Stroke: The four major physiological variables that must be monitored and managed are blood pressure, arterial blood gas levels, body temperature, and glycaemia. The effects of controlling these physiological variables have not been studied in prospective trials, though they may all contribute to the outcome of acute ischaemic stroke and affect the duration of the therapeutic window. Optimal physiological parameters are inherently neuroprotective. Trials of new agents for the treatment of acute stroke should aim to maintain these physiological variables as close to normal as possible, and certainly within strictly defined limits. The Place of Neuroprotectants in Acute Stroke Management: Stroke patients are a very heterogeneous group with respect to stroke mechanisms and severity, general condition, age and co-morbidities. At the present time, the only firm guideline than can be proposed for patient selection is the need for early admission to enable neuroprotectant and/or thrombolytic treatment to be started as soon as possible within the therapeutic window. The severity of potential side-effects will largely determine who should assess a patient with suspected stroke and initiate treatment. There is little information on which to base the duration of neuroprotectant therapy, and more experimental data are needed. Even if prehospital treatment proves to be feasible, it should not replace comprehensive stroke management in a specialist hospital unit. Clinical trials of neuroprotectants should only be performed in stroke units. The combined approach of restoring blood flow and providing neuroprotection may be the most productive in human stroke, but current clinical trial design will have to change in order to test combination therapy. Important side-effects are those that interfere with any possible benefit or increase mortality. Pharmaco-Economic Aspects of Neuroprotectants: The early increase in hospital costs associated with neuroprotectant therapy may be balanced by the shorter length of hospital stay and lesser degree of disability of the surviving patients. The overall direct financial cost is highly dependent on the number of patients eligible for neuroprotectant therapy, which is itself dependent on the length of the therapeutic window and the severity of potential side-effects. A treatment that achieves a good functional outcome is the most cost-effective approach.


Seizure-european Journal of Epilepsy | 2005

Incidence of epilepsy and predictive factors of epileptic and non-epileptic seizures

Irene A.W. Kotsopoulos; Marc C. T. F. M. de Krom; Fons Kessels; Jan Lodder; J. Troost; Mascha Twellaar; Tiny van Merode; André Knottnerus

PURPOSE To estimate the incidence of unprovoked seizures (US) and epilepsy in a general population from the southern part of the Netherlands, in relation to age, sex, etiology and seizure type, and to identify predictive factors of the epileptic and non-epileptic seizures. METHODS All patients aged > or =14 years with a first seizure or who had undiagnosed seizures before the study period were included. Patients were identified from different sources and were independently evaluated and classified by a team of neurologists. A predictive profile for the occurrence of epileptic and non-epileptic seizures was obtained by stepwise logistic regression analysis. RESULTS The overall annual incidence was 55/100,000 and 30/100,000 for US and epilepsy, respectively. The age-specific annual incidence of US and epilepsy increased with age and reached 120/100,000 and 62/100,000 for the > or =65 years of age group, respectively. The incidence of epilepsy and US in males was higher than in females and partial seizures prevailed over generalized seizures (40 versus 9/100,000). In up to 35% of the cases with US or epilepsy, the etiology was mainly cerebrovascular disease and brain tumors. Predictors for epileptic versus non-epileptic seizures of organic origin were an epileptiform EEG pattern (OR=0.06) versus a history of hypertension (OR=2.8) or cardiovascular disease (OR=5.4). Strong predictors for seizures of non-organic origin were female sex (OR=2.2) and head injury (OR=2.4). CONCLUSIONS The incidence of US and epilepsy (overall, and age-, sex-, seizure-specific) was similar to those reported by other developed countries. The predictive factors found in this study may assist in the early diagnosis of seizures.

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Jan Lodder

Maastricht University Medical Centre

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J. Lodder

Maastricht University

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J. Troost

Maastricht University

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Anita Boreas

Maastricht University Medical Centre

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Gert-Jan Luijckx

University Medical Center Groningen

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Jelis Boiten

Western General Hospital

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