T Karlsson

Two sites for modulation of human sympathetic activity by arterial baroreceptors

1 Peroneal muscle sympathetic nerve activity (MSA), finger blood pressure and cardiac intervals were recorded at rest in 60 healthy subjects, aged 18–71 years. Arterial baroreflex control of MSA was analysed by relating each spontaneous sympathetic burst to the diastolic blood pressure and the cardiac interval of the heart beat during which the burst was generated. The results were expressed as blood pressure/cardiac interval threshold for occurrence of bursts, and as baroreflex sensitivity (i.e. the relationship between diastolic pressure/cardiac interval and burst strength). 2 Significant blood pressure/cardiac interval thresholds were present in all subjects and old subjects had less variability of thresholds than young subjects. In contrast, significant baroreflex sensitivity for diastolic pressure and cardiac interval was present in only 55 and 73 % of the subjects, respectively. There was no age‐related difference in sensitivity. 3 In 40 subjects, two 5 min periods from the same recording were analysed. The number of sympathetic bursts and the threshold for occurrence of bursts were reproducible in all subjects. In contrast, significant baroreflex sensitivity in both periods was present in only 30 % (diastolic pressure) and 40 % (cardiac interval) of the subjects. 4 The results show that the baroreflex mechanisms regulating the occurrence and strength of sympathetic bursts are not identical. We suggest that the modulation occurs at two sites, one which determines whether or not a burst will occur, and another at which the strength of the discharge is determined.

Are patients truthful about their smoking habits? A validation of self-report about smoking cessation with biochemical markers of smoking activity amongst patients with ischaemic heart disease.

Abstract. From Attebring M, Herlitz J, Berndt A‐K, Karlsson T, Hjalmarson A (Division of Cardiology, Sahlgrenska University Hospital, Göteborg, Sweden). Are patients truthful about their smoking habits? A validation of self‐report about smoking cessation with biochemical markers of smoking activity amongst patients with ischaemic heart disease. J Intern Med 2001; 249: 145–151.

Determinants of an impaired quality of life five years after coronary artery bypass surgery

OBJECTIVE To identify determinants of an inferior quality of life (QoL) five years after coronary artery bypass grafting (CABG). SETTING University hospital. PARTICIPANTS Patients from western Sweden who underwent CABG between 1988 and 1991. MAIN OUTCOME MEASURES Questionnaires for evaluating QoL before CABG and five years after operation. Three different instruments were used: the Nottingham health profile (NHP), the psychological general wellbeing index (PGWI), and the physical activity score (PAS). RESULTS 2121 patients underwent CABG, of whom 310 died during five years’ follow up. Information on QoL after five years was available in 1431 survivors (79%). There were three independent predictors for an inferior QoL with all three instruments: female sex, a history of diabetes mellitus, and a history of chronic obstructive pulmonary disease. Multivariate analysis showed that a poor preoperative QoL was a strong independent predictor for an impaired QoL five years after CABG. An impaired QoL was also predicted by previous disease. CONCLUSIONS Female sex, an impaired QoL before surgery, and other diseases such as diabetes mellitus are independent predictors for an impaired QoL after CABG in survivors five years after operation.

Distress correlates with the degree of chest pain: a description of patients awaiting revascularisation.

AIM: To describe various symptoms other than pain among consecutive patients on the waiting list for possible coronary revascularisation in relation to estimated severity of chest pain. DESIGN: All patients were sent a postal questionnaire for symptom evaluation. SUBJECTS: All patients in western Sweden on the waiting list in September 1990 who had been referred for coronary angiography or coronary revascularisation (n = 904). RESULTS: 88% of the patients reported chest pain symptoms that limited their daily activities to a greater or lesser degree. Various psychological symptoms including anxiety and depression were strongly associated with the severity of pain (P < 0.001), as were sleep disturbances (P < 0.001), and dyspnoea and various psychosomatic symptoms (P < 0.001). Nevertheless only 44% of the patients reported chest pain as the major disruptive symptom, whereas the remaining 56% reported uncertainty about the future, fear, or unspecified symptoms as being the most disturbing. CONCLUSIONS: In a consecutive series of patients on the waiting list for possible coronary revascularisation, half the participants reported that uncertainty and fear were more disturbing than chest pain.

Improvement in quality of life differs between women and men after coronary artery bypass surgery

Abstract. Sjöland H, Wiklund I, Caidahl K, Hartford M, Karlsson T, Herlitz J (Sahlgrenska University Hospital, Göteborg, and Astra Hässle AB, Mölndal, Sweden). Improvement in quality of life differs between women and men after coronary artery bypass surgery. J Intern Med 1999; 245: 445–454.

Factors associated with pre-hospital and in-hospital delay time in acute myocardial infarction: a 6-year experience.

Berglin Blohm M, Hartford M, Karlsson T, Herlitz J (Division of Cardiology, Sahlgrenska University Hospital, Göteborg, Sweden). Factors associated with pre‐hospital and in‐hospital delay time in acute myocardial infarction: a 6‐year experience. J Intern Med 1998; 243: 243–50.

C-reactive protein, interleukin-6, secretory phospholipase A2 group IIA and intercellular adhesion molecule-1 in the prediction of late outcome events after acute coronary syndromes.

Objective.  We investigated whether levels of C‐reactive protein (CRP), interleukin‐6 (IL‐6), secretory phospholipase A2 group IIA (sPLA2‐IIA) and intercellular adhesion molecule‐1 (ICAM‐I) predict late outcomes in patients with acute coronary syndromes (ACS).

Arteriovenous anastomoses and the thermoregulatory shift between cutaneous vasoconstrictor and vasodilator reflexes

The reflex changes in skin blood flow which occur in response to various non-thermal stimuli (e.g., deep inspiratory gasps, arousing or painful stimuli, emotional stress) are profoundly influenced by the thermoregulatory state. The aim of the present study was to evaluate the involvement of arteriovenous anastomoses in the thermoregulatory modulation of skin vasomotor reflexes elicited by painful intraneural electrical stimulation and emotional stress (forced arithmetics), respectively. Vasomotor responses were recorded with laser Doppler flowmeters (LDF) placed on glabrous skin containing arteriovenous anastomoses (3rd finger and thenar eminence) and hairy skin which lack them (dorsal side of the first metacarpal bone). In some experiments, a laser Doppler flowmeter emitting laser light of two different wavelengths (infrared and green light) into the same skin site was used to record skin perfusion at different depths of glabrous skin on the thenar eminence. 40 subjects were investigated, both in the cold state (finger skin temperatures below 25 degrees C) and after subsequent warming (finger skin temperatures above 30 degrees C). Thermoregulatory modulation of electrical stimulation- or stress-induced vasomotor reflexes occurred both in glabrous and hairy skin, but hairy skin differed from glabrous skin by showing no significant vasoconstrictions. Relative perfusion changes were most marked in laser Doppler flowmeter recordings using the deeper penetrating infrared light. The results suggest that arteriovenous anastomoses are major contributors to the vasoconstrictor component of vasomotor reflexes in glabrous skin of warm subjects. The reflex increase in perfusion, on the other hand, which occurs in both glabrous and hairy skin of cold subjects may be mediated by resistance vessels.

Serum lipids, lipoprotein(a) and apo(a) isoforms in patients with established coronary artery disease and their relation to disease and prognosis after coronary by-pass surgery

Consecutive patients (n=964) undergoing coronary angiography were studied and compared with a random population sample regarding serum lipids and lipoproteins with focus on lipoprotein(a) (Lp[a]) levels and apo(a) isoforms. The patients were also followed for 5 years after the angiography, and the prognostic value of serum lipoproteins were analyzed. The patients were divided in two groups: Group 1 (n=814) consisted of patients with angina pectoris and at least one coronary artery with 50% stenosis and group 2 (n=150) patients with none of the coronary arteries significantly obstructed ( < 50%). As controls a random population sample was selected (n=197). Blood samples were collected before coronary angiography for determination of serum lipids, Lp(a) and isoforms of apo(a). When group 1 and group 2 patients were compared, group 1 was found to have higher serum cholesterol, triglycerides, apoB and Lp(a) as well as lower HDL and apoAI. When group 1 was compared with the random sample, after correction for age and sex, similar differences were observed, except that the difference in Lp(a) was not significant. The high Lp(a) levels among patients was found to be primarily due to the female patients, where the difference compared to both group 2 and controls was highly significant (P=0.007 and P=0.001, respectively). There was a significant difference in the apo(a) isoform distribution between group 1 patients and control subjects (P=0.0003), with a higher frequency of low molecular weight isoforms among patients. This was also significant for the male subgroup (P=0.001). Lp(a), LDL, total cholesterol, triglycerides. apoB, HDL and apoAI were significantly related to the number of major coronary arteries with > 50% stenosis. Mortality during follow-up was,in a univariate analysis, significantly correlated to several factors related to the degree of heart disease and to LDL (P=0.02) and apoB (P < 0.01). Increased mortality was, however, related to low levels of apoB and LDL. For cardiac mortality no significant correlation to lipoprotein variables were found. In conclusion established lipoprotein risk factors were more frequent among patient with angina pectoris and verified coronary stenosis. Furthermore high Lp(a) levels and a high frequency of low molecular weight isoforms of apo(a) were found in coronary patients. Higher Lp(a) levels were observed both for female and male patients, the differences were, however, significant only for the female patients. None of the lipoprotein variables could predict coronary death during the follow-up period.

A media campaign aiming at reducing delay times and increasing the use of ambulance in AMI

To improve the prognosis in patients with acute myocardial infarction (AMI) if treatment by early instituting treatment, we initiated a media campaign during 1 year with the intention to reduce delay times and increase ambulance use in patients with acute chest pain. This article describes the outcome during 3 years after the campaign was finished. The median delay time in patients with AMI was reduced from 3 hours 0 min before the campaign to 2 hours 20 minutes during the year of the campaign (P < .001). The median delay time remained at a similar level (2 hours 20 min) during the 3 years after the campaign. Ambulance use was not affected during or after the campaign. It can be concluded that a media campaign resulted in a reduction of delay times not only during the campaign, but also during 3 years after its performance, whereas ambulance use was not affected.