Diurnal Blood Pressure Changes Research Articles

Diurnal Blood Pressure Change Following Stroke is Related to Long Term Outcome

Diurnal Blood Pressure Change Following Stroke is Related to Long Term Outcome

Predictors of diurnal blood pressure changes in 2042 subjects with essential hypertension

To determine the independent predictors of day-night blood pressure changes in a large population of subjects with essential hypertension. We studied 2042 white untreated subjects with essential hypertension (mean age 52 years, range 17-93, 1052 men) who underwent 24 h ambulatory blood pressure monitoring on an outpatient basis. Night-time workers were excluded from analysis. For both sexes, the changes in systolic and diastolic blood pressures from day to night decreased progressively with age and increased with the reported duration of sleep. The 1207 employed subjects who underwent ambulatory blood pressure monitoring during a usual working day had greater day-night blood pressure differences than did those who did not work (16.2 versus 14.0%). By using multiple regression analysis we assessed the independent association of several variables with the diurnal blood pressure changes. Age and diabetes for both sexes, and clinic blood pressure in men, were inversely associated with the nocturnal fall in blood pressure. The duration of sleep and the occurrence of blood pressure monitoring during a normal work day predicted a greater day-night blood pressure difference for both sexes; smoking predicted a greater nocturnal fall in blood pressure for women. Age is associated with an important and progressive attenuation of the day-night blood pressure difference in untreated and unrestricted subjects with essential hypertension. Other factors influencing diurnal blood pressure variations include clinic blood pressure, diabetes, the reported duration of sleep, smoking habits and working activity during blood pressure monitoring. These factors should be treated as potential confounders in the analysis of the relationship between diurnal blood pressure changes and target organ damage or prognosis.

Rate adaptive pacing in sick sinus syndrome: effects of pacing modes and intrinsic conduction on physiological responses, arrhythmias, symptomatology and quality of life

An atrial-based pacing mode is superior to ventricular constant rate demand pacing (VVI) mode in patients with sick sinus syndrome (SSS) by providing both rate adaptation and atrioventricular (AV) synchrony. The use of a non-atrial sensor to overcome chronotropic incompetence and preserve normal intrinsic AV conduction in pacemaker therapy for SSS was investigated in 15 consecutive patients (mean age 66 +/- 2 years). All had intact AV conduction (antegrade conduction capacity > 100 beats.min-1 and an atrial paced to intrinsic R interval of < or = 220 ms). DDDR pacemakers capable of being programmed into atrial rate adaptive (AAIR), dual chamber rate adaptive (DDDR) and ventricular rate adaptive (VVIR) modes were used. Beginning with an acute study, arterial pressure was invasively assessed in each pacing mode during physiological stresses and low level exercise. In the ambulatory phase, the incidence of ventricular pacing and arrhythmias (Holter recording), diurnal blood pressure changes (ambulatory blood pressure recording), and symptom and quality of life level (questionnaires and interviews) were compared. Despite similar heart rate changes during acute physiological stresses, a higher blood pressure was recorded during AAIR or DDDR pacing compared with VVIR pacing. Systolic blood pressure over 24 h was lower in the VVIR mode (122 +/- 5 mmHg) than AAIR/DDDR pacing (129 +/- 6/128 +/- 6 mmHg, P < 0.05). VVIR pacing was associated with a higher frequency of atrial and ventricular ectopics, with two patients developing paroxysmal atrial fibrillation. Ventricular pacing was used in a higher percentage in the DDDR compared with the VVIR mode (64 +/- 11 and 39 +/- 7%, P < 0.03). VVIR pacing was associated with more palpitations, a lower level of general well being and depression. Despite the use of a sensor to overcome chronotropic incompetence, VVIR pacing is a less satisfactory pacing mode for SSS. Although AAIR/DDDR pacing may achieve similar haemodynamic and clinical status, in patients with intact AV conduction, AAIR pacing may be preferable by avoiding an abnormal ventricular activation pattern.

Efficacy of combination therapy with a calcium antagonist and an angiotensin converting enzyme inhibitor in hypertensive patients

We have been examining diurnal blood pressure changes for various antihypertensive drugs to characterize their hypotensive effects on 24-hour blood pressure values. The present study evaluated blood pressure control using a combination of nitrendipine, a calcium antagonist, and cilazapril, an angiotensin converting enzyme inhibitor, administered once daily to 10 patients with essential hypertension who had casual blood pressure readings of 160/95 mmHg or higher measured on two different drug-free days. After receiving nitrendipine 10 mg or cilazapril 1 mg once daily in the morning for more than 4 weeks, none of the patients showed a sufficient reduction in blood pressure. A combination of nitrendipine 10 mg and cilazapril 1 mg was then administered once daily in the morning, and 24-hour blood pressure was recorded 2 weeks later. Satisfactory blood pressure reduction was achieved in the patients who did not respond adequately to cilazapril or nitrendipine alone. Analysis of diurnal blood pressure changes revealed that the patients who did not respond to a single drug had high nocturnal blood pressure values and a more severe type of hypertension. Analysis of cumulative percentages revealed that the decrease in the range of high values (the 90% value) was large but that the decrease in the range of low values (the 10% value) was small. These findings suggest that the combination of nitrendipine and cilazapril is an ideal therapy that reduces blood pressure in a manner similar to physiologic blood pressure changes.

Exercise Heart Rate During Beta-Blockade

This study tried to determine the diurnal exercise heart rate (HR) changes in trained subjects with coronary artery disease who were either chronically medicated with beta-blockers or were nonmedicated control patients. There were 6 patients in the atenolol group, 5 patients in the metoprolol group, and 11 patients in the control group. All subjects undertook symptom-limited maximal exercise tolerance tests (ETT) by cycle ergometry 2 hours after administering medication for exercise prescription and four submaximal cycle ergometer training sessions at 1, 4, 8, and 12 hours after medication administration. HR, systolic blood pressure, diastolic blood pressure, and rate of perceived exertion (RPE) were recorded at rest, 30 watts (W), 60 W, and target training HR work loads. Blood plasma lactate levels were evaluated at target training HR work loads. Data were analyzed by repeated analysis of variance (ANOVA). When significant differences were found, the Neuman-Keuls test was applied to identify at what times differences occurred. Control patients showed no significant diurnal changes for HR, systolic blood pressure, diastolic blood pressure, rate-pressure product (RPP), RPE, or plasma lactate at rest, 30 W, 60 W, or target training HR work load. Patients in the metoprolol group demonstrated significant HR fluctuations at rest, 30 W, and 60 W, whereas differences for patients in the atenolol group occurred at rest and at 30 W only. At target training HR, the work loads varied significantly over time for the atenolol and metoprolol groups, but RPE varied significantly only for the metoprolol group. Blood plasma lactate levels did not fluctuate significantly for either group. Significant diurnal changes in systolic blood pressure were exhibited only by the atenolol group at 30 W and 60 W. Only the metoprolol group cycling at 30 W exhibited significant variations for diastolic blood pressure. Significant RPP changes were found for the atenolol and metoprolol groups at 30 W and 60 W, but not at target training HR. It appeared that both medications provided a similar degree of beta-blockade 1 to 4 hours after medication was administered. However, atenolol provided more attenuation in the cardiovascular response than did metoprolol during later-day stationary cycle exercise (8 to 12 hours after medication administration).