Observation of high enantioselectivity for the gas phase hydrogenation of methyl pyruvate using supported Pt catalysts pre-modified with cinchonidine

Pt supported on alpha-Al2O3, gamma-Al2O3 and SiO2 pre-modified with cinchonidine gives over 50% ee in the hydrogenation of methyl pyruvate to methyl lactate using gas phase reactants at 40 degrees C giving the first clear observation of high enantioselection at the gas/solid interface.

Social work practice with people with disabilities in the era of disability rights

Social workers, especially those in health care and rehabilitation systems, must consider practice changes necessitated by recent legislation and the growing activism of disability rights groups. The authors review essential elements of the emerging sense of both oppression and empowerment that is occurring for many people with disabilities and groups; consider key aspects of ADA and other perti nent legislation that place new emphases on the self-determination of people with disabilities; and discuss what implications changing practice roles might have for social workers' relationships and patterns of interaction with other professionals in medical, health care and rehabilitation settings. The authors outline a beginning effort at designing a conceptual framework that promotes practice that: (1) maximizes clients' involvement in exploring an expanded range of options and choices; (2) prepares clients to be more effective in dealings with professionals, bureaucrats and agencies that often do not understand nor appreciate their need for self-determination; and (3) at the organizing level, mobilizes and helps to empower groups of people with disabilities to consider policy and program alternatives that can improve their situation. This framework may also be useful in work with people who have other long term care needs, chronic conditions.

Diuretic therapy in congestive heart failure

The principal goals of treatment of the patient in heart failure are the relief of their symptoms and improvement in their prognosis. Of all antiheart failure drugs currently available, the diuretics are therapeutically superior in their efficacy in relieving clinical symptoms and signs. Whether administered intravenously or orally, all diuretics result in a substantial reduction in the raised pulmonary vascular pressures in combination with a small reduction in cardiac output. Diuretics stimulate release of renin with subsequent activation of the renin-angiotensin-aldosterone system, particularly if used in large doses, although their quantitative impact on the neuroendocrine profile at different stages of heart failure remains to be defined. In patients with mild heart failure, diuretics reduce plasma catecholamine concentrations, but their sympatholytic effects in more severe cases are unknown, as are their effects on the metabolically active tissues in these patients. Diuretic resistance can be circumvented by segmental nephron blockade with a combination of low-dose diuretics that simultaneously block sodium reabsorption in the proximal tubule, the loop of Henle, the distal tubule, and the collecting duct. Diuretics improve symptoms of breathlessness and signs of peripheral edema in patients with congestive heart failure in direct relationship to the induced diuresis. These benefits are frequently associated with a substantial improvement in patients' appreciation of quality of life and economic capacity. There are few adverse reactions to chronic diuretic therapy, but the serum electrolytes should be monitored for hypokalemia and hypomagnesemia. The impact of diuretics on prognosis of patients with congestive heart failure is unknown; however, diuretics have been a major ingredient of the therapies used in all the survival trials with vasodilators, angiotensin-converting enzyme inhibitors, and beta-blocking drugs. In addition to their clinical benefits, diuretics are the most cost-effective treatment of any single drug group currently available for the treatment of patients with congestive heart failure.

Diuretics in cardiovascular therapy: the new clinicopharmacological bases that matter

Diuretics in current use include early distal tubular (i.e., thiazide-type), loop (i.e., furosemide-type), and potassium-and-hydrogen-retaining substances. Available oral formulations of diuretics differ in terms of their renal excretory potency in man, as formally assessed through the effect of a single dose on 24-hour natriuresis in healthy subjects. The 2.5 mg formulation of the loop diuretic torasemide does not increase mean 24-hour natriuresis, and it is therefore considered a very-low-dose formulation. Amiloride 5 mg and torasemide 5 mg and 10 mg, which increase mean 24-hour natriuresis by less than 40%, are considered low-dose or low-potency diuretic formulations of diuretic substances. Hydrochlorothiazide 25 and 50 mg, furosemide 40 and 80 mg, and torasemide 20 mg, which increase mean 24-hour natriuresis by more than 40%, are considered high-dose or high-potency formulations. A rebound in natriuresis follows the early-after-dosing increase in this variables caused by loop diuretics; hence many oral formulations of loop substances are less potent natriuretics than most oral formulations of thiazide-type diuretics. Hydrochlorothiazide 25 mg and furosemide 80 mg have similar natriuretic potencies. During once-daily administration of diuretic formulations of diuretics to subjects without edema and normal renal function, the increases in 24-hour natriuresis and diuresis that follow the first dose disappear or attenuate markedly. This is due to neuroendocrine reactions to diuretic-induced sodium loss and its attendant hemodynamic shifts. Some of these reactions, e.g. the increase in plasma aldosterone that takes place, account for an elevation in kaliuresis that occurs during once-daily treatment with a high-dose formulation of a thiazide-type diuretic. Common fixed-dose combinations of a thiazide-type or a loop diuretic and a potassium-and-hydrogen-retaining substance generally do not change kaliuresis, but they increase natriuresis strikingly. Thiazide-type and loop diuretics decrease and increase calciuresis respectively; none of these actions wanes during prolonged administration. Plasma renin activity and aldosterone do not rise in response to very-low-dose formulations of loop diuretics taken once daily. Glomerular filtration rate tends to fall in the course of once-daily administration of high-dose formulations of diuretics, but not during prolonged once-daily treatment with very-low-dose formulations of loop diuretics.

Hemodynamic differences between metoprolol and carvedilol in hypertensive patients

Resting hemodynamics were measured before, at 2 and 24 h after the first dose, and after 4 weeks of monotherapy with either metoprolol or carvedilol in a randomized single-blind study. We analyzed results from 24 hypertensive patients (30-68 years of age) with adequate blood-pressure lowering on monotherapy. Acutely, both drugs lowered systolic blood pressure and heart rate. Whereas metoprolol reduced cardiac output and increased both systemic and femoral artery resistance, carvedilol did not alter cardiac output but led to reductions in the systemic and regional resistances. After 4 weeks of therapy, cardiac output remained reduced and vascular resistances increased in the metoprolol group, whereas in carvedilol patients cardiac output continued to be unchanged and the trend for vascular resistances to be decreased persisted. Acutely and chronically the differences in the hemodynamic effects of the two medications were statistically significant. The study results indicate that carvedilol's vasodilatory action is not subject to tolerance development. Chronic afterload reduction associated with the decrease in systemic vascular resistance may lead to additional savings in myocardial oxygen consumption, a beneficial feature particularly in those patients with concomitant ischemic heart disease. It may also have a favorable influence on concentric cardiac hypertrophy and changes in the walls of arteriolar resistance vessels.

Comparison of the hemodynamic effects of metoprolol and carvedilol in hypertensive patients

Metoprolol and carvedilol are widely used in the treatment of hypertension, but no randomized comparison of their hemodynamic activity has been previously reported. Their comparative effects on heart rate, systemic blood pressure, and echocardiographically determined aortic and femoral artery blood flow were measured at rest and at 2 and 24 hours after the first dose of each drug, and again after 4 weeks of sustained monotherapy in 12 male and 12 female patients, aged 36-68 years with uncomplicated sustained hypertension according to a randomized single-blind protocol. Nine patients in each drug group achieved the target diastolic blood pressure of < 90 mmHg on the initial doses of each drug; this was achieved in the remainder following doubling of each dose. Neither drug occasioned withdrawal of any patient due to adverse reactions. Both drugs significantly reduced heart rate, although the reduction at 2 hours was significantly greater after metoprolol than after carvedilol. Both drugs reduced systolic pressure throughout the study; the reduction at 2 hours was significantly greater after carvedilol than after metoprolol. In contrast, the diastolic blood pressure was persistently reduced only by carvedilol. The cardiac output, determined as the aortic systolic blood flow, after carvedilol was not significantly different from pretreatment values throughout the study but was significantly reduced in the metoprolol-treated patients at each point of measurement. After metoprolol the systemic and femoral vascular resistances derived from conventional formulae were consistently and significantly increased over pretreatment values throughout the study and were significantly greater than in the carvedilol group at all measurement points. The hemodynamic differences between these two beta-blocking drugs may be explained by the additional vasodilator activity of carvedilol associated with its alpha 1-adrenoceptor blocking activity. The long-term clinical and prognostic implications of these pharmacodynamic differences between beta-adrenoceptor antagonists with and without additional vasodilator activity in the treatment of hypertensive patients remain to be determined.

Congestive heart failure. Towards a comprehensive treatment

Heart failure constitutes an increasing health hazard with major demands on health care resources. Recent major advances in drug treatment have yet to be translated into increased survival of heart failure patients in the community at large. Failure of diagnosis is a major factor in delaying early and adequate treatment. Echocardiography probably provides the most reliable and inexpensive instrument to confirm the diagnosis and pinpoint the mechanical components of the syndrome. The targets for therapeutic intervention may be categorized (i) haemodynamic, neuroendocrine and metabolic disorders (ii) symptoms and quality of life, (iii) morbidity and mortality risks. Symptoms and quality of life are the prime concerns of the physician in the treatment in the individual patient. Selection of anti-heart failure drugs used should be based on knowledge of the impact on the pathophysiological disorders and on the morbidity and mortality risks. Diuretics, vasodilators and ACE-inhibitors are now accepted as standard treatment, particularly when used in combination. Controversy continues to surround the efficacy of digitalis glycosides; they improve symptoms in some patients but their impact on morbidity and mortality risks is still uncertain. Even with standard treatments, may practical therapeutic questions remain, one of which is what is the most efficacious dose of each anti-heart failure drug which, when used in combination, will give the maximum improvement in quality of life and greatest extension of survival? Despite available treatment with diuretics, digitalis, vasodilators and ACE-inhibitors, the morbidity and mortality risks of congestive heart failure remain high. None of these drug groups significantly modulates the excessive excitation of the sympathoadrenal system, one of the two major neuroendocrine hazards of heart failure. For this reason, amongst the many newer drugs in development, the beta-adrenoceptor antagonists hold considerable promise as the next step towards a more comprehensive treatment of congestive heart failure.

Reoperation for recurrent metastatic brain tumors

Results of reoperation in 48 patients who developed recurrent brain metastases between January 1984 and April 1993 are presented. Median time from first craniotomy to diagnosis of recurrence (time to recurrence) was 6.7 months. Median Karnofsky performance scale (KPS) score prior to reoperation was 80. Recurrence was local in 30 patients, distant in 16 patients, and both local and distant in two patients. Median survival time after reoperation was 11.5 months. There were no operative mortalities. Multivariate analysis revealed that presence of systemic disease (p = 0.008), KPS scores less than or equal to 70 (p = 0.008), time to recurrence of less than 4 months (p = 0.008), age greater than or equal to 40 years (p = 0.51), and primary tumor type of breast or melanoma (p = 0.028) negatively affected patient survival time. These five factors were used to develop a grading system (Grades I-IV). Patients categorized in Grade I had a 5-year survival rate of 57%, whereas the median survival time of patients in Grades II, III, and IV was 13.4, 6.8, and 3.4 months, respectively (p < 0.0001). Overall, 26 patients developed a second recurrence after reoperation. Seventeen patients underwent a second reoperation, whereas nine did not. Patients undergoing a second reoperation survived a median of 8.6 additional months versus 2.8 months for those who did not (p < 0.0001). This study concludes that reoperation for recurrent brain metastasis can prolong survival and improve quality of life. A second reoperation can also increase survival. Five factors influence survival: status of systemic disease, KPS score, time to recurrence, age, and type of primary tumor. The grading system using these five factors correlates with survival time. Reoperation should be approached with caution in Grade IV patients because of their poor prognosis.

Refocus on diuretics in the treatment of heart failure

Diuretics have long been accepted as the traditional first-line treatment of the patient with symptomatic heart failure whatever its aetiology or dysfunctional stage. Their acceptance in this role is based on the rapid improvement in congestive symptoms experienced by most patients, which is arguably greater than that induced by any other currently available anti-heart failure drug. This symptomatic efficacy and their universal clinical acceptance as first-step treatment for the patient with symptoms of heart failure has precluded formal examination of their impact on prognosis. Evidence from indirect studies suggests that when used alone they may not be able to prevent clinical deterioration, possibly due to excitation of the renin-angiotensin-aldosterone system. When such excitation is suppressed by concomitant administration of angiotensin-converting enzyme inhibitors, relief of congestive symptoms is enhanced and the morbidity and mortality risk of heart failure significantly reduced. Studies on the mechanisms of diuretic resistance have demonstrated the synergy of diuretic activity when low doses of diuretics acting at different sites of the nephron are used in combination. Diuretics remain the cornerstone of treatment for symptoms in congestive heart failure but their overall efficacy is substantially improved when combined with ACE inhibitors.

Sarcoma metastatic to the brain: results of surgical treatment

We report on 21 patients surgically treated for intraparenchymal brain metastasis from sarcoma, including six osteosarcomas, four leiomyosarcomas, three malignant fibrous histiocytomas, two alveolar soft-part sarcomas, two Ewing's bone sarcomas, one extraskeletal osteosarcoma, one extraskeletal Ewing's sarcoma, and two unclassified sarcomas. Median survival after craniotomy was 11.8 months. Patients with a preoperative Karnofsky performance score of > 70 survived for 15.7 versus 6.6 months for those with a Karnofsky performance score < or = 70. Patients. undergoing complete resection survived 14.0 versus 6.2 months for patients undergoing incomplete resection. Patients with evidence of lung metastases at the time of surgery survived 11.8 months, which was similar to the 10.5-month survival for patients with disease limited to the brain. The two patients with alveolar soft-part sarcoma are alive at 16 and 25 months after surgery. We conclude that surgery is effective in treating selected patients with sarcoma metastatic to the brain and that patients with metastasis from alveolar soft-part sarcoma may have a relatively good prognosis if they are surgically treated. The complete removal of all brain metastases and a Karnofsky performance score > 70 are associated with a favorable prognosis, whereas the presence of concurrent lung metastases is not a contraindication to surgery.

Effect of pregnancy on prognosis for young women with breast cancer

Breast cancer in women under 30 years old carries a poor prognosis, for reasons that have not been identified. This study aimed to identify prognostic factors in this age group. Special attention was paid to the history of pregnancy. The clinical presentation and course of breast cancer was documented for 407 women, aged 20-29 years, who registered between 1978 and 1988 at one of nine cancer centres. Eligible patients had histologically confirmed local or regional invasive breast carcinoma, and received part or all of their initial therapy at the participating hospital. For patients whose breast cancers were diagnosed during pregnancy, the risk of dying from breast cancer was significantly greater than that of women who had never been pregnant (relative risk 3.26 [95% CI 1.81-5.87], p = 0.0004). Adjustment for number of axillary nodes affected and tumour diameter reduced the relative risk only slightly (2.83 [1.24-6.45], p = 0.023). For each 1-year increment in the time between the latest previous pregnancy and breast cancer diagnosis, the risk of dying decreased by 15% (relative risk 0.85, p = 0.011). Thus concurrent or recent previous pregnancy adversely affects survival of breast cancer in young women. The size of the effect is such that it probably contributes substantially to the poor prognosis of breast cancer in this age group as a whole.

Occurrence and prognosis of contralateral carcinoma of the breast

Of the 4,554 patients who registered at The University of Texas M. D. Anderson Cancer Center, Houston, Texas from 1965 to 1988 with a diagnosis of carcinoma of the breast and who underwent surgical treatment of at least one carcinoma of the breast at this institution, 142 had either a history of a prior carcinoma of the breast (metachronous; n = 55) or a contralateral carcinoma of the breast detected within four months of registration (synchronous; n = 87). We retrospectively studied the records of these 142 patients and found that the occurrence of bilateral carcinoma of the breast was low (3.1 percent), the frequency of metachronous carcinoma of the breast remained relatively constant over time, the nodal status of the second carcinoma of the breast correlated with the method of discovery rather than the stage of the first carcinoma of the breast and survival rates from the second carcinoma of the breast were similar for metachronous and synchronous disease. These data support the role of vigilant surveillance of the contralateral breast with screening at the time of initial diagnosis and during follow-up evaluation. Because the likelihood of detecting a second carcinoma of the breast at an early stage is high, with subsequent good survival rates, the use of prophylactic mastectomy should be very selective and based on the emotional needs of the patient.

Usefulness of amlodipine for angina pectoris

Calcium antagonists are effective antianginal agents in the treatment of patients with stable exercise-induced angina pectoris. A series of randomized, double-blind, placebo-controlled studies with the novel, once-daily calcium antagonist amlodipine have been completed in a large number of patients with stable exercise-induced angina pectoris. Compared with placebo, once-daily amlodipine demonstrated a significant dose-related extension in exercise duration and workload accomplished, and reduction in number of anginal attacks and associated glyceryl trinitrate consumption. The clinical antianginal attributes of amlodipine were accompanied by significant reductions in electrocardiographic evidence of myocardial ischemia. In comparison with other antianginal drugs, once-daily amlodipine at a dosage range of 5-10 mg demonstrated antianginal activity comparable to thrice-daily diltiazem and once-daily nadolol. Amlodipine administered once daily achieves symptomatic and electrocardiographic amelioration of myocardial ischemic episodes induced by exercise in the majority of patients with stable angina pectoris. Amlodipine does not depress left ventricular pumping activity, and its side-effect profile does not differ substantially from that of placebo.

Double-blind comparison of amlodipine and nifedipine retard in the treatment of mild to moderate hypertension

The efficacy and safety profiles of amlodipine (5-10 mg once daily) and nifedipine retard (20-40 mg twice daily) were compared in 111 hypertensive patients (sitting DBP in 95-115 mmHg) during eight weeks of treatment in a randomised double-blind parallel group study. BP was measured 22-24 hours after the daily dose of amlodipine and 10-12 hours after a dose of nifedipine retard. Baseline sitting BPs of 175/105 mmHg and 168/104 mmHg were significantly reduced (P < 0.05) to 157/93 mmHg and 151/92 mmHg at the end of treatment in response to mean daily doses of amlodipine 7.3 mg and nifedipine retard 58.9 mg. There were no clinically significant changes in heart rate with either treatment. Three patients in the amlodipine group and five patients in the nifedipine retard group could not be considered in analysis. The total numbers of adverse events (considered related or possibly related to treatment) (42 vs. 36) as well as the numbers of patients experiencing such events (22 vs. 22) were similar in the amlodipine and nifedipine retard treated groups, respectively, but with a greater incidence of headaches in response to nifedipine retard and of oedema in response to amlodipine. Five patients in each treatment group discontinued therapy due to such events. Overall the results showed once daily amlodipine as equivalent to twice daily nifedipine retard in the management of mild to moderate hypertension.

Captopril versus digoxin in patients with coronary artery disease and mild heart failure. A prospective, double-blind, placebo-controlled multicenter study. The CADS Study Group

We conducted a prospective, double-blind, placebo-controlled multicenter trial in order to evaluate the long-term effects of captopril (50 mg/day), digoxin (0.25 mg/day) and placebo on quality of life, cardiovascular events, clinical symptoms and exercise tolerance in patients with documented myocardial infarction, resulting in regional wall motion abnormalities, and with mild heart failure (NYHA class II to III without treatment) and exercise not limited by angina. 222 patients were studied, 63 were randomized to captopril, 66 to digoxin, 67 to placebo. Follow-up was conducted for two years. Base line characteristics in the three treatment groups were similar. After one year of therapy, digoxin had significantly improved general well-being (p < 0.01 vs captopril), symptom score (p < 0.05 vs captopril and placebo), and vitality (p < 0.05 vs captopril). Digoxin improved NYHA class in 45% as compared to placebo (28%, p < 0.05). Worsening of angina was more frequent with captopril as compared to digoxin (p < 0.05). However, cardiovascular events during follow-up were lower in the captopril group as compared to placebo and digoxin (p < 0.01 captopril vs placebo). No differences between groups were observed in baseline and follow-up exercise tolerance between the three groups. Dizziness during upright tilt and cough were more frequent with captopril as compared to digoxin or placebo. After two years of follow-up (captopril n = 32, digoxin n = 29, placebo n = 27) general well-being was improved with both digoxin and captopril (p < 0.004 and p < 0.03 vs placebo).(ABSTRACT TRUNCATED AT 250 WORDS)

Diuretics in postinfarction heart failure

Severe left ventricular failure, as evidenced by radiographic pulmonary edema or raised left ventricular filling pressure, accompanying acute myocardial infarction, carries a high mortality risk. In this situation, the intravenous loop-diuretic furosemide induces a rapid reduction in the raised left ventricular filling pressure due to an immediate and substantial increase in systemic venous compliance accompanied by increasing diuresis. This diuretic-induced venodilatation is probably due to the release of prostaglandins. The transient systemic arterial constriction and small increase in systemic blood pressure that follows intravenous furosemide probably results from the release of renin and subsequent activation of angiotensin. These diuretic induced hemodynamic changes are accompanied by restoration of the vasodilator reflex, which enables the heart to accommodate an acute volume load. Orally administered loop diuretics achieve slower, but similar, directional hemodynamic changes. There is no information on hemodynamic or neuroendocrine dose-response effects of loop diuretics, and there is no information pertaining to the use of other diuretic groups in this situation. The hemodynamic changes induced by furosemide summate with the changes induced by other anti-heart-failure drugs. In this subset of patients with acute myocardial infarction and severe heart failure, the influence of the diuretics on morbidity incidence and mortality risk remains to be measured.

Impact of adjuvant mitotane on the clinical course of patients with adrenocortical cancer

BACKGROUND

Adrenocortical carcinoma is a rare and aggressive disease with a poor prognosis. Adjuvant mitotane administration has been suggested as a strategy that might improve the outcome of patients with localized disease.

METHODS

The authors analyzed the clinical outcome of patients with localized or regional adrenocortical cancer. The study included 19 patients who were registered at M.D. Anderson Cancer Center during a 3-year period and who had localized or regional disease at the time of surgery. Of these, eight patients received mitotane postoperatively and continued the drug until their last contact or recurrence (Group A, adjuvant); five patients began taking mitotane after surgery but discontinued it after 2-12 months for reasons unrelated to the disease (Group P, postoperative); and six patients did not receive mitotane (Group N, no mitotane). All patients have been followed for at least 12 months.

RESULTS

The treatment groups differed significantly in their time to recurrence; the disease-free interval was shortest in Group A (P = 0.0055, by log-rank test). There was no statistical difference in survival among the groups, but the profile remained unfavorable for Group A. The 2-year survival rate was 100% for Groups N and P but only 43% for Group A. Of the potentially confounding factors, gender, age, steroid hypersecretion, and tumor size, none had any influence on recurrence or survival rates.

CONCLUSIONS

These findings do not support the conclusion that adjuvant mitotane is beneficial in patients with localized or regional adrenocortical cancer. Neither the disease-free interval nor survival was improved by the drug. The authors suggest that alternative therapeutic strategies be explored for the management of these patients.

Incidence of hypercalcemia in patients with malignancy referred to a comprehensive cancer center

BACKGROUND

Hypercalcemia is a serious and not infrequent complication of malignant diseases; precise information about the incidence of hypercalcemia is not readily available. The study was designed to determine the incidence of hypercalcemia in patients with cancer.

METHODS

Retrospective analysis was done of laboratory data from 7667 patients registered at M.D. Anderson Cancer Center for the first time during 1989 for whom serum calcium levels were determined during the first 2 months after registration.

RESULTS

Severe hypercalcemia (serum calcium level of more than 12.0 mg/100 ml) was present in 40 patients (0.52%); it occurred most often in patients with renal cell cancer (1.42%) and non-small cell lung cancer (1.03%). Less frequent diagnoses were multiple myeloma (0.79%), leukemia (0.63%), non-Hodgkin lymphoma (0.26%), and cancer of the gastrointestinal tract (0.20%). Moderate hypercalcemia (calcium levels of 10.8-12.0 mg/100 ml) was present in 48 patients (0.63%); it occurred most often in patients with renal cell cancer (3.30%) and multiple myeloma (2.38%). Less frequent diagnoses were non-small cell lung cancer (0.89%), non-Hodgkin lymphoma (0.79%), leukemia (0.63%), and cancer of the gastrointestinal tract (0.51%). The presence of hypercalcemia was associated with increased frequency of distant metastases, bone metastases, and increased mortality consistent with other studies of the prognostic effect of this complication.

CONCLUSIONS

Hypercalcemia may appear as a frequent complication in patients with cancer at some time during the course of their disease, but its incidence is relatively low.

Incidence of hypercalcemia in patients with malignancy referred to a comprehensive cancer center

BACKGROUND

Hypercalcemia is a serious and not infrequent complication of malignant diseases; precise information about the incidence of hypercalcemia is not readily available. The study was designed to determine the incidence of hypercalcemia in patients with cancer.

METHODS

Retrospective analysis was done of laboratory data from 7667 patients registered at M.D. Anderson Cancer Center for the first time during 1989 for whom serum calcium levels were determined during the first 2 months after registration.

RESULTS

Severe hypercalcemia (serum calcium level of more than 12.0 mg/100 ml) was present in 40 patients (0.52%); it occurred most often in patients with renal cell cancer (1.42%) and non-small cell lung cancer (1.03%). Less frequent diagnoses were multiple myeloma (0.79%), leukemia (0.63%), non-Hodgkin lymphoma (0.26%), and cancer of the gastrointestinal tract (0.20%). Moderate hypercalcemia (calcium levels of 10.8-12.0 mg/100 ml) was present in 48 patients (0.63%); it occurred most often in patients with renal cell cancer (3.30%) and multiple myeloma (2.38%). Less frequent diagnoses were non-small cell lung cancer (0.89%), non-Hodgkin lymphoma (0.79%), leukemia (0.63%), and cancer of the gastrointestinal tract (0.51%). The presence of hypercalcemia was associated with increased frequency of distant metastases, bone metastases, and increased mortality consistent with other studies of the prognostic effect of this complication.

CONCLUSIONS

Hypercalcemia may appear as a frequent complication in patients with cancer at some time during the course of their disease, but its incidence is relatively low.

Early side-effects of antihypertensive therapy: comparison of amlodipine and nifedipine retard

In a multicentre crossover study of 97 patients with mild hypertension, the incidence and severity of adverse effects were observed during the first 14 days of treatment with amlodipine, nifedipine retard or placebo. Amlodipine (5 mg) once daily was equipotent to nifedipine retard (20 mg) twice daily. At these doses, the incidence of adverse effects was significantly greater during treatment with nifedipine retard (41%) than with amlodipine (27%, P < 0.05) or placebo (16%, P < 0.01). In particular, headache and flushing occurred significantly less frequently during the first 14 days of treatment with amlodipine than with nifedipine retard. The lower incidence and reduced severity of vasodilatory side-effects associated with amlodipine resulted in fewer withdrawals during initiation of therapy (2 on amlodipine compared with 7 on nifedipine retard).

Diuretics in heart failure: some knowns and unknowns

There are many hemodynamic faces of heart failure, ranging from the subclinical to the terminal syndrome. The diuretics possess, with minor qualification, the pharmacotherapeutic attributes of the ideal first-line drug of choice. In heart failure, the loop diuretics have achieved eminence due to their improvement of the deranged hemodynamic profile without significant adverse pharmacologic effects. The new loop diuretics, including torasemide, have been shown to reduce the raised pulmonary vascular pressures without significant depression of the cardiac output in patients with chronic heart failure. This hemodynamic improvement has been paralleled by a significant improvement in clinical symptoms in the majority of patients. The undoubted and widely accepted efficacy of the loop diuretics in all the heart failure syndromes have presented a formidable ethical obstacle to their formal testing in terms of improvement in exercise capacity and reduction of mortality risk. There is still a paucity of information on their singular impact on the excited neuroendocrine reflexes in heart failure and their influence on the widespread metabolic disturbances occasioned by pumping failure of the heart. From the clinical standpoint, however, these deficiencies in information do nothing to reduce the importance of the loop diuretics in the treatment of acute and chronic heart failure.

Vasodilator therapy for acute heart failure: haemodynamic comparison of hydralazine/isosorbide, alpha-adrenoceptor blockade, and angiotensin-converting enzyme inhibition

Haemodynamic comparison of three vasodilation regimens [intravenous (i.v.) hydralazine and isosorbide dinitrate (ISDN) combined, i.v. doxazosin, and i.v. enalaprilat] was undertaken in 36 patients with acute left ventricular (LV) failure due to recent myocardial infarction. Each regimen achieved similar reductions in pulmonary artery occluded pressure (PAOP, preload) and systemic arterial pressures (afterload), with increased cardiac and stroke volume (SV) indexes (p less than 0.01). Only the hydralazine and isosorbide combination induced resting tachycardia. Balanced vasodilatation after selective alpha-adrenoceptor blockade (doxazosin) and angiotensin-converting enzyme (ACE) inhibition (enalaprilat) without increase in heart rate (HR) suggests that these therapies may have definite haemodynamic advantages over the hydralazine/ISDN combination.

Therapeutic targets in ischaemic heart disease

The adequate treatment of a disease syndrome is dependent upon a clear definition of the symptomatic, pathological, physiological and prognostic targets against which therapy is to be deployed. The syndromes of ischaemic heart disease, including angina pectoris, are complex in origin, pathology, pathophysiology and natural history, and a complete clinical profile is difficult, if not impossible, to achieve in individual patients. The prime goals of pharmacotherapy in ischaemic heart disease are easy to define, but difficult to accomplish in practice. Relief of pain, breathlessness and fatigue are the prime clinical targets for pharmacotherapy. In view of their sinister significance, the electrophysiological indications of myocardial ischaemia, whether symptomatic or silent, are also crucial targets towards which therapy must be directed. Ischaemic heart disease is accompanied by a wide variety of regional and global abnormalities of myocardial contractile function associated with widespread reflex stimulation of the peripheral vascular system and neuroendocrine systems. Primarily, drug therapy must be directed at correction of these pathophysiological components of the syndrome. Longer term but no less essential goals in the treatment of ischaemic heart disease are the prevention of the clinical sequelae of the syndrome and its progression. A natural sequel of coronary artery obstructive disease is successive thrombotic events and loss of myocardium. Calcium antagonists, by preventing the increase in myocardial cytosolic calcium during acute ischaemic episodes, defer cell necrosis; in this respect, they are unique among currently available antianginal drugs. With regard to progression, the prime pathological cause of ischaemic heart disease is coronary atheroma.(ABSTRACT TRUNCATED AT 250 WORDS)

Amlodipine in post-infarction angina

Once-daily administration of amlodipine is a highly effective treatment for patients with angina pectoris. This study has confirmed its benefit in a relatively large subgroup of patients with post-myocardial infarction angina. Amlodipine reduced the number of angina attacks and nitroglycerin consumption and substantially improved the ability of the patient to perform physical exercise. The circadian pattern of angina attacks was markedly attenuated by amlodipine with patients reporting fewer attacks during the mid-morning peak that was clearly evident at baseline. The advantage of once-daily dosing, together with the excellent control of angina achieved in post-infarction patients, make amlodipine a good choice for therapy.

Modulation of inotropic therapy by venodilation in acute heart failure: a randomised comparison of four inotropic agents, alone and combined with isosorbide dinitrate

The effects of four inotropic agents with differing ancillary properties [a cardiac glycoside (digoxin), a combined alpha- and beta-adrenergic agonist (dobutamine), a beta-adrenergic agonist (prenalterol), and a phosphodiesterase inhibitor (amrinone)] alone and with subsequent addition of isosorbide dinitrate were compared in 48 consecutive acute myocardial infarction patients with radiographic and haemodynamic (pulmonary artery occluded pressure greater than 18 mm Hg) left ventricular failure. All agents with the exception of dobutamine reduced the elevated left heart filling pressure; only digoxin and dobutamine augmented the cardiac stroke volume index. All drugs except digoxin reduced the SVRI; an arteriolar constrictor response was evident 60 min after digoxin and a tachycardia resulted after combined alpha- and beta- and beta-adrenergic stimulations (dobutamine and prenalterol, respectively). The addition of isosorbide dinitrate reversed the inotrope-induced elevations of systemic arterial pressure and resulted in additional reductions in left heart filling pressure. These data suggest that, in the absence of substantial venodilator properties in an inotropic compound, reduction in elevated left heart filling pressure is not achieved with inotropic therapy alone in acute left ventricular failure and combining a venodilator may be haemodynamically advantageous.

Comparison of early side effects with amlodipine and nifedipine retard in hypertension

The frequency and severity of adverse effects during the first 14 days of treatment with amlodipine (5 mg once daily), nifedipine retard (20 mg twice daily) or placebo were compared in a multicentre, three-way, cross-over study involving 97 patients with mild-to-moderate hypertension. All three groups of patients were well matched for age, sex and baseline blood pressure. Amlodipine and nifedipine retard produced highly significant and comparable reductions in blood pressure, indicating that the doses were therapeutically equivalent. The incidence of adverse effects considered to be definitely or probably related to nifedipine retard treatment (41%) was significantly higher than for placebo (16%, p less than 0.01) or amlodipine (27%, p less than 0.05). There were no significant differences in the incidence of vasodilator-related adverse effects between amlodipine and placebo. In contrast, headache, flushing and dizziness were reported more frequently by patients while on nifedipine retard than on placebo or amlodipine. The convenience of once-daily dosing, together with a lower incidence of adverse effects, with consequently fewer withdrawals from therapy, suggests that amlodipine has clinical advantages over nifedipine retard in the treatment of hypertension.

Treatment of ischemic heart disease in the 1990s: key issues for the physician

During recent years, understanding of the basic pathology, pathophysiology, and morbid risk of ischemic heart disease has increased immensely, but a wide gulf still exists between such knowledge and its practical application to the individual patient. Although the treatment of ischemic heart disease continues to pose many dilemmas for the physician in the 1990s, the key issues are easy to define, particularly with regard to pharmacotherapy. The basic pathologic processes and their rate of development and progression, their pathophysiologic consequences, and their morbidity and mortality risks are becoming increasingly clear. Until methods are developed to reconstitute the obstructed coronary arteries, clinical attention must be directed primarily to alleviating symptoms and ECG signs of myocardial ischemia and improving the deranged hemodynamic disorder. These primary objectives are now achievable with modern anti-ischemic drugs such as nicorandil. With the availability of efficacious drugs against clinical symptoms, ECG signs, and hemodynamic associates of ischemic heart disease, clinical attention must be redirected to retardation or even regression of the primary myocardial ischemic syndrome. This therapeutic goal can be achieved only by correction of the secondary risk factors that are present in many patients with ischemic heart disease. Only by such a comprehensive approach, namely, that of treatment allied to prevention, can the gap between knowledge and its practical application to the individual patient be narrowed.(ABSTRACT TRUNCATED AT 250 WORDS)

Efficacy of doxazosin in specific hypertensive patient groups

In practice, some of the major problems for the physician who treats hypertension are patients who are resistant to treatment or who have other complicating risk syndromes. Therefore the overall efficacy of an antihypertensive agent must include an assessment of effect in patients with serious ancillary problems. In this article, doxazosin is reviewed for its efficacy in the treatment of severe essential hypertension and specific complications or conditions of mild or moderate essential hypertension, namely, left ventricular hypertrophy, hyperlipidemia, noninsulin-dependent diabetes mellitus, renal insufficiency, pheochromocytoma, chronic obstructive pulmonary disease, peripheral vascular disease, and smoking. Doxazosin is particularly efficacious in many specific subgroups of patients with hypertension, and the results of relevant studies are discussed.

Efficacy and safety of doxazosin in the treatment of patients with mild or moderate essential hypertension and elevated levels of cholesterol

In hypertensive patients, elevated serum cholesterol is a frequent and sinister additional coronary risk factor. Selective alpha 1-adrenoreceptor inhibitors appear to have the unique ability to control both risk factors. Forty-two patients, ages 42 to 65 years, including 21 men with sustained hypertension and elevated serum cholesterol levels, were included in a trial of monotherapy with doxazosin administered once daily (range, 1 to 16 mg). The influence of the drug on high blood pressure and elevated serum cholesterol was evaluated over a 28-week period, which consisted of a 4-week, single-blind placebo lead-in period, an open 10-week dose-adjustment period, and finally a 14-week maintenance period. Of the 39 efficacy-evaluable patients, 25 (64%) achieved adequate blood pressure control (diastolic blood pressure less than 90 mm Hg or a decrease in diastolic blood pressure greater than 10 mm Hg) at a mean daily dose of 2 mg of doxazosin. No persistent changes occurred in heart rate. In the 32 patients with evaluable lipid data, there were nonsignificant trends to an increase in high-density lipoprotein cholesterol and a reduction in total cholesterol, together with a significant reduction in serum triglyceride concentration. The combined changes in blood pressure and blood lipid levels resulted in a reduction of 36% in the calculated risk of coronary heart disease. Eleven patients reported side effects and four were withdrawn from therapy. These results confirm the antihypertensive and anticholesterolemic efficacy of once-daily treatment with doxazosin.(ABSTRACT TRUNCATED AT 250 WORDS)

Efficacy of ibopamine in the treatment of heart failure

Loss of myocardial contractility, reflexly enhanced vasoconstriction, and neuroendocrine excitation are the pathophysiologic hallmarks of low-output heart failure. Drugs that counter both consequences afford considerable therapeutic potential in retarding and perhaps even in staying the consequences of the syndrome. Ibopamine possesses such potential through its unique ability to stimulate both dopaminergic- and beta-adrenoreceptors in the heart and circulatory system. Stimulation of dopaminergic- receptors and beta 2-adrenoreceptors results in vasodilatation in all regional vascular territories. beta 2-Adrenoreceptor agonist activity also affords mild positive inotropic activity in the heart, whereas stimulation of presynaptic dopaminergic- receptors (DA2) attenuates the increased sympathetic neural outflow. The drug also suppresses the renin-angiotensin-aldosterone system in addition to having a direct natriuretic activity. The pharmacodynamic effects of ibopamine, exerted through its metabolite epinine, are translated into measurable therapeutic benefits in patients with chronic heart failure. The increase in peripheral blood flow induced in all regional vascular territories, including the kidneys, is associated with increased cardiac output and stroke volume and reduction in left ventricular pressure work, wall stress, and myocardial oxygen consumption. Plasma norepinephrine, angiotensin, and aldosterone are also reduced, and renal sodium excretion is enhanced. These hemodynamic and neuroendocrine activities, which are not subject to tolerance during sustained administration of the drug, are accompanied by clinically significant improvement in symptoms, exercise tolerance, and the New York Heart Association classification of disability. More important, no proarrhythmic effects have been observed during sustained treatment, and the minimal side effects observed during long-term treatment enhance the safety profile of the drug.(ABSTRACT TRUNCATED AT 250 WORDS)

Management of vascular risk factors in the hypertensive patient

Understanding of the multiple risk factors for premature vascular degeneration is essential for the most effective management of the hypertensive patient. High blood pressure is the most important single predictor of coronary heart disease risk in general clinical practice in the UK. However, hypertension is only a marker of an apparent excess of other risk factors for coronary heart disease among hypertensive patients. The global management of the patient is further complicated for two reasons. First, many of the risk factors are complexly interrelated, either biologically or by lifestyle. Second, the attempted correction of one factor is fraught with the potential for aggravation of the others. The benefits to the coronary and vascular risk profile from lowering blood pressure may be offset, partially or completely, by the aggravation of other risk factors by the antihypertensive drug used. Optimum management of the hypertensive patient can only be achieved when all the risk factors for coronary heart disease in that individual are modified.

How does posture influence the haemodynamic assessment of a cardiovascular drug? Experience with nicardipine

The extent to which posture altered the haemodynamic response to slow calcium channel blocker nicardipine was evaluated in 22 male patients with angiographically confirmed coronary artery disease. Patients were randomly allocated to supine or upright posture and an otherwise identical protocol performed in each group. At rest, following a control saline period, four doses of the drug (log cumulative dosage: 1.25, 2.5, 5.0, and 10.0 mg) were administered by i.v. infusion over a total period of 40 min; haemodynamic indices were recorded during the 3-5 min following each 5 min infusion. The exercise effects of the drug, in each posture, were determined by comparison of a control predrug exercise with observations at the same workload following the maximal cumulative dose. Nicardipine reduced resting mean blood pressure (MBP) and systemic vascular resistance index (SVRI) in both postures, the decrease being more pronounced when upright (MBP, -12%, -18%; p less than 0.01: SVRI, -30%, -46%; p less than 0.01). The increases in cardiac index (CI) and stroke volume index (SVI) were higher when upright (29 and 54% vs. 10 and 27%; p less than 0.01). Pulmonary artery occluded pressure (PAOP) increased by 29% when upright, without change when supine. On exercise, the effects for HR, MBP, CI, SI, and SVRI responses were independent of posture; however, a qualitative difference was apparent for PAOP (-17% vs. +14%; p less than 0.05). Thus, although the actions of nicardipine were qualitatively similar, quantitative differences related to posture were confirmed. These differences appeared to relate to posture-related baseline haemodynamic differences between the groups but with similar postnicardipine absolute values.