Evaluation and treatment of patients with systemic hypertension

Primary Prevention of Coronary Heart Disease in the Elderly

OBJECTIVE:

To review relevant literature supporting the use of antihypertensive agents, lipid-lowering agents (i.e., statins), and aspirin therapy for the primary prevention of coronary heart disease (CHD) in an elderly patient population (age ≥65 y).

DATA SOURCES:

A MEDLINE search (1988–January 2003) was conducted.

STUDY SELECTION AND DATA EXTRACTION:

Primary and tertiary literature involving the uses of antihypertensives, statins, and aspirin therapy in the elderly were reviewed.

DATA SYNTHESIS:

Mortality due to CHD in the US population has decreased 40–50% over the last 30 years; however, CHD remains the leading cause of morbidity and mortality in elderly persons. As the population continues to age, the number of older adults eligible for primary prevention will rise. The American Heart Association clinical practice guidelines for the primary prevention of CHD were updated in 2002; however, they are based on findings from clinical trials that enrolled predominantly middle-aged white men. The recommendations for elderly individuals are predominantly extrapolated from subgroup analyses of randomized clinical trials or cohort studies. This literature suggests that elderly persons are candidates for primary prevention measures and experience reductions in coronary events when treated with appropriate therapies.

CONCLUSIONS:

Data suggest that use of antihypertensives, statins, and aspirin therapy in the elderly appears effective to an extent similar to, and often greater than, that observed in younger patients. We believe these agents should be prescribed to all appropriate high-risk elderly patients. Ongoing and future studies will more clearly elucidate the benefits of primary prevention therapy, particularly in persons ≥75 years of age.

Common medical illnesses that affect anesthesia and their anesthetic management

Patients undergoing an office-based anesthetic require a thorough preoperative evaluation to identify medical illnesses and undertake appropriate investigations or studies. This article addresses common medical illnesses seen in oral surgery offices and provides insight into their anesthetic management, concentrating on open-airway office-based anesthesia.

Renal sympathetic denervation: MDCT evaluation of the renal arteries

OBJECTIVE

Percutaneous transluminal renal sympathetic denervation is a new treatment of refractory systemic hypertension. The purpose of this study was to assess the clinical utility of MDCT to evaluate the anatomic configuration of the renal arteries in the context of renal sympathetic denervation.

MATERIALS AND METHODS

Two readers retrospectively evaluated the MDCT renal artery scans of 90 patients (mean age, 70 ± 13 years; range, 32-98 years). Analysis included the number of renal arteries on each side, ostial shape and size, angle off the aorta, branching pattern, degree of tortuosity, and distance to adjacent vascular structures.

RESULTS

Sixty-five patients had one, 23 had two, and two had three renal arteries on one side. One hundred forty-six arteries were funnel-shaped (72 left and 74 right; mean ostial diameter, 0.9 ± 0.2 cm tapering to 0.6 ± 0.1 cm). The mean tortuosity index was 1.1 (range, 1 [no tortuosity] to 3.1). Compared with the left renal artery, the right renal artery was longer (4.0 ± 0.9 cm vs 5.0 ± 1.2 cm, p ≤ 0.001), originated at a more acute angle on axial (67° vs 98°, p < 0.05) and coronal images (57° ± 16° vs 65° ± 14°, p < 0.05), was significantly closer to the superior mesenteric artery (1.0 ± 0.7 cm vs 1.6 ± 1.2 cm, p < 0.001), and came in closer contact with venous structures (0.0 ± 0.1 vs 0.2 ± 0.9, p < 0.05).

CONCLUSION

Our findings suggest MDCT of the renal arteries is an informative investigation in patients undergoing renal sympathetic denervation, providing data on the number and size of renal branches, ostial shape, and proximity to adjacent venous structures.

2-Aryl- and 2-amido-benzothiazoles as multifunctional vasodilators on rat artery preparations

The neuroprotective agent riluzole [2-amino-6-(trifluoromethoxy)benzothiazole] has been shown to antagonize neuronal high-voltage activated Ca(2+) currents. In the search for novel scaffolds leading to potential antihypertensive agents, a series of 2-aryl- and 2-amido-benzothiazoles (HUP) were assessed for their vasorelaxing property on rat aorta rings and for their L-type Ba(2+) currents [I(Ba(L))] blocking activity on single myocytes isolated from the rat tail artery. HUP5 and HUP30, the most potent of the series, inhibited phenylephrine-induced contraction with IC₅₀ values in the range 3-6 µM. The presence of endothelium did not modify their spasmolytic activity. Both HUP5 and HUP30 increased tissue levels of cGMP and shifted to the left the concentration-response curve to sodium nitroprusside. In rings precontracted by phenylephrine, tetraethylammonium or 1H-[1,2,4] oxadiazolo [4,3-a] quinoxalin-1-one (ODQ) shifted to the right the concentration-relaxation curves of HUP5 and HUP30. The antispasmodic effect of HUP5 and HUP30 was more marked on rings stimulated with 25/30 mM than with 60 mM K(+). HUP5 and HUP30 antagonized both extracellular Ca(2+) influx and Ca(2+) mobilization from intracellular stores in response to phenylephrine: this effect was not modified by the presence of ODQ. I(Ba(L)) was partly inhibited by HUP5 and blocked by HUP30 in a concentration-dependent as well as ODQ-independent manner. In conclusion, HUP5 and HUP30 are vasorelaxing agents that stimulate soluble guanylyl cyclase, activate K(+) channels, and block extracellular Ca(2+) influx. The present benzothiazole derivatives form a novel class of multifunctional vasodilators which may give rise to effective antihypertensive agents.

Drug-induced atrioventricular block: prognosis after discontinuation of the culprit drug

OBJECTIVES

The goal of this study was to determine how often atrioventricular (AV) block is really caused by medications.

BACKGROUND

Beta-blockers, verapamil, and diltiazem are considered a cause of AV block for which pacemaker implantation is not indicated. However, it is not known if such patients can expect a benign course after discontinuation of the culprit medication.

METHODS

Consecutive patients with II or III degree AV block not related to acute myocardial infarction, digitalis toxicity, or vasovagal syncope were studied. The level of AV block (AV-nodal or infranodal) was defined by electrocardiographic criteria. The cause and effect relation between AV block and drugs was defined according to the response to drug discontinuation.

RESULTS

Of 169 patients with AV block, 92 (54%) were receiving beta-blockers and/or verapamil or diltiazem. Patients receiving medications had similar clinical and electrocardiographic characteristics with patients who had AV block in the absence of drugs. Drug discontinuation was followed by resolution of AV block in 41% of cases, whereas spontaneous improvement of AV conduction occurred in 23% of patients who had AV block in the absence of drugs. However, 56% of the patients for whom drug discontinuation led to resolution of AV block had recurrence of AV block in the absence of therapy. Atrioventricular block that was "truly caused by drugs" was found in only 15% of patients who had II or III degree AV block during therapy with beta-blockers, verapamil, or diltiazem.

CONCLUSIONS

Atrioventricular block is commonly "related to drugs" but is rarely "caused by drugs."

Hypertension in adolescents: a review of diagnosis and management

Long-term hypertension contributes to significant cardiovascular and renal morbidity and mortality. Although chronic hypertension is much rarer in the adolescent population than in adults, identifying the hypertensive adolescent and intervening with risk factors such as obesity that may promote hypertension is important for the clinician treating adolescents. Since both primary and secondary causes of hypertension may exist in the adolescent, a thorough and sequential clinical and diagnostic evaluation must be undertaken, including screening urinalysis, blood chemistries, and renal sonography. There are pitfalls in interpreting casual blood pressure measurements in adolescents, and the role of ambulatory blood pressure monitoring is evolving. Lifestyle modifications, including diet, exercise, and limitation of sodium intake, remain the foundation of treatment. Commonly used medications include calcium channel blockers, angiotensin receptor blockers and converting enzyme inhibitors, beta blockers, and diuretics. When considering medication in the hypertensive adolescent, potential complications of therapy must be reviewed in light of the physical and psychosocial changes ongoing in this age group.