Antithrombotic and thrombolytic therapy for valvular disease: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines

BACKGROUND

Antithrombotic therapy in valvular disease is important to mitigate thromboembolism, but the hemorrhagic risk imposed must be considered.

METHODS

The methods of this guideline follow those described in Methodology for the Development of Antithrombotic Therapy and Prevention of Thrombosis Guidelines. Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines in this supplement.

RESULTS

In rheumatic mitral disease, we recommend vitamin K antagonist (VKA) therapy when the left atrial diameter is > 55 mm (Grade 2C) or when complicated by left atrial thrombus (Grade 1A). In candidates for percutaneous mitral valvotomy with left atrial thrombus, we recommend VKA therapy until thrombus resolution, and we recommend abandoning valvotomy if the thrombus fails to resolve (Grade 1A). In patients with patent foramen ovale (PFO) and stroke or transient ischemic attack, we recommend initial aspirin therapy (Grade 1B) and suggest substitution of VKA if recurrence (Grade 2C). In patients with cryptogenic stroke and DVT and a PFO, we recommend VKA therapy for 3 months (Grade 1B) and consideration of PFO closure (Grade 2C). We recommend against the use of anticoagulant (Grade 1C) and antiplatelet therapy (Grade 1B) for native valve endocarditis. We suggest holding VKA therapy until the patient is stabilized without neurologic complications for infective endocarditis of a prosthetic valve (Grade 2C). In the first 3 months after bioprosthetic valve implantation, we recommend aspirin for aortic valves (Grade 2C), the addition of clopidogrel to aspirin if the aortic valve is transcatheter (Grade 2C), and VKA therapy with a target international normalized ratio (INR) of 2.5 for mitral valves (Grade 2C). After 3 months, we suggest aspirin therapy (Grade 2C). We recommend early bridging of mechanical valve patients to VKA therapy with unfractionated heparin (DVT dosing) or low-molecular-weight heparin (Grade 2C). We recommend long-term VKA therapy for all mechanical valves (Grade 1B): target INR 2.5 for aortic (Grade 1B) and 3.0 for mitral or double valve (Grade 2C). In patients with mechanical valves at low bleeding risk, we suggest the addition of low-dose aspirin (50-100 mg/d) (Grade 1B). In valve repair patients, we suggest aspirin therapy (Grade 2C). In patients with thrombosed prosthetic valve, we recommend fibrinolysis for right-sided valves and left-sided valves with thrombus area < 0.8 cm(2) (Grade 2C). For patients with left-sided prosthetic valve thrombosis and thrombus area ≥ 0.8 cm(2), we recommend early surgery (Grade 2C).

CONCLUSIONS

These antithrombotic guidelines provide recommendations based on the optimal balance of thrombotic and hemorrhagic risk.

Prevention of rheumatic fever and diagnosis and treatment of acute Streptococcal pharyngitis: a scientific statement from the American Heart Association Rheumatic Fever, Endocarditis, and Kawasaki Disease Committee of the Council on Cardiovascular Disease in the Young, the Interdisciplinary Council on Functional Genomics and Translational Biology, and the Interdisciplinary Council on Quality of Care and Outcomes Research: endorsed by the American Academy of Pediatrics

Primary prevention of acute rheumatic fever is accomplished by proper identification and adequate antibiotic treatment of group A beta-hemolytic streptococcal (GAS) tonsillopharyngitis. Diagnosis of GAS pharyngitis is best accomplished by combining clinical judgment with diagnostic test results, the criterion standard of which is the throat culture. Penicillin (either oral penicillin V or injectable benzathine penicillin) is the treatment of choice, because it is cost-effective, has a narrow spectrum of activity, and has long-standing proven efficacy, and GAS resistant to penicillin have not been documented. For penicillin-allergic individuals, acceptable alternatives include a narrow-spectrum oral cephalosporin, oral clindamycin, or various oral macrolides or azalides. The individual who has had an attack of rheumatic fever is at very high risk of developing recurrences after subsequent GAS pharyngitis and needs continuous antimicrobial prophylaxis to prevent such recurrences (secondary prevention). The recommended duration of prophylaxis depends on the number of previous attacks, the time elapsed since the last attack, the risk of exposure to GAS infections, the age of the patient, and the presence or absence of cardiac involvement. Penicillin is again the agent of choice for secondary prophylaxis, but sulfadiazine or a macrolide or azalide are acceptable alternatives in penicillin-allergic individuals. This report updates the 1995 statement by the American Heart Association Rheumatic Fever, Endocarditis, and Kawasaki Disease Committee. It includes new recommendations for the diagnosis and treatment of GAS pharyngitis, as well as for the secondary prevention of rheumatic fever, and classifies the strength of the recommendations and level of evidence supporting them.

Echocardiography screening for rheumatic heart disease in Ugandan schoolchildren

BACKGROUND

Historically, sub-Saharan Africa has had the highest prevalence rates of clinically detected rheumatic heart disease (RHD). Echocardiography-based screening improves detection of RHD in endemic regions. The newest screening guidelines (2006 World Health Organization/National Institutes of Health) have been tested across India and the Pacific Islands, but application in sub-Saharan Africa has, thus far, been limited to Mozambique. We used these guidelines to determine RHD prevalence in a large cohort of Ugandan school children, to identify risk factors for occult disease, and to assess the value of laboratory testing.

METHODS AND RESULTS

Auscultation and portable echocardiography were used to screen randomly selected schoolchildren, 5 to 16 years of age, in Kampala, Uganda. Disease likelihood was defined as definite, probable, or possible in accordance with the 2006 National Institutes of Health/World Health Organization guidelines. Ninety-seven percent of eligible students received screening (4869 of 5006). Among them, 130 children (2.7%) had abnormal screening echocardiograms. Of those 130, secondary evaluation showed 72 (55.4%) with possible, probable, or definite RHD; 18 (13.8%) with congenital heart disease; and 40 (30.8%) with no disease. Echocardiography detected 3 times as many cases of RHD as auscultation: 72 (1.5%) versus 23 (0.5%; P<0.001). Children with RHD were older (10.1 versus 9.3 years; P=0.002). Most cases (98%) involved only the mitral valve. Lower socioeconomic groups had more RHD (2.7% versus 1.4%; P=0.036) and more advanced disease (64% versus 26%; P<0.001). Antistreptolysin O titers were elevated in children with definite RHD.

CONCLUSIONS

This is one of the largest single-country childhood RHD prevalence studies and the first to be conducted in sub-Saharan Africa. Our data support inclusion of echocardiography in screening protocols, even in the most resource-constrained settings, and identify lower socioeconomic groups as most vulnerable. Longitudinal follow-up of children with echocardiographically diagnosed subclinical RHD is needed.

Gingival hyperplasia caused by nifedipine--a preliminary report

We observed marked gingival hyperplasia, similar clinically and histologically to the hyperplasia caused by 5:5 sodium diphenylhydantoin (Dilantin) during the last 18 months in five patients treated by nifedipine. Histologically, marked epithelial hyperplasia-acanthosis, with moderate inflammatory reaction in the lamina propria, was observed in all the biopsy specimens. Evidence points to a strong relationship between the gingival hyperplasia and the administration of nifedipine.

Secondary Antibiotic Prophylaxis for Latent Rheumatic Heart Disease

BACKGROUND

Rheumatic heart disease affects more than 40.5 million people worldwide and results in 306,000 deaths annually. Echocardiographic screening detects rheumatic heart disease at an early, latent stage. Whether secondary antibiotic prophylaxis is effective in preventing progression of latent rheumatic heart disease is unknown.

METHODS

We conducted a randomized, controlled trial of secondary antibiotic prophylaxis in Ugandan children and adolescents 5 to 17 years of age with latent rheumatic heart disease. Participants were randomly assigned to receive either injections of penicillin G benzathine (also known as benzathine benzylpenicillin) every 4 weeks for 2 years or no prophylaxis. All the participants underwent echocardiography at baseline and at 2 years after randomization. Changes from baseline were adjudicated by a panel whose members were unaware of the trial-group assignments. The primary outcome was echocardiographic progression of latent rheumatic heart disease at 2 years.

RESULTS

Among 102,200 children and adolescents who had screening echocardiograms, 3327 were initially assessed as having latent rheumatic heart disease, and 926 of the 3327 subsequently received a definitive diagnosis on the basis of confirmatory echocardiography and were determined to be eligible for the trial. Consent or assent for participation was provided for 916 persons, and all underwent randomization; 818 participants were included in the modified intention-to-treat analysis, and 799 (97.7%) completed the trial. A total of 3 participants (0.8%) in the prophylaxis group had echocardiographic progression at 2 years, as compared with 33 (8.2%) in the control group (risk difference, -7.5 percentage points; 95% confidence interval, -10.2 to -4.7; P<0.001). Two participants in the prophylaxis group had serious adverse events that were attributable to receipt of prophylaxis, including one episode of a mild anaphylactic reaction (representing <0.1% of all administered doses of prophylaxis).

CONCLUSIONS

Among children and adolescents 5 to 17 years of age with latent rheumatic heart disease, secondary antibiotic prophylaxis reduced the risk of disease progression at 2 years. Further research is needed before the implementation of population-level screening can be recommended. (Funded by the Thrasher Research Fund and others; GOAL ClinicalTrials.gov number, NCT03346525.).

Maintenance of cardiac output with normal filling pressures in patients with dilated heart failure

Therapy of elevated ventricular filling pressures in patients with dilated heart failure may be limited by concern that cardiac output will be further compromised. Twenty-five patients with severe symptoms and ejection fractions of 25% or less were studied to determine the lowest ventricular filling pressures that could be achieved with vasodilator and diuretic therapy while maintaining cardiac output. In 20 of 25 patients normal pulmonary capillary wedge pressures (PCWs) were achieved (mean 10 mm Hg compared with 30 mm Hg at baseline). Stroke volume was 60 vs 39 ml at baseline. Stroke work index was 30 vs 19 g-m/m2. For each patient, over the range of PCWs, stroke volume and stroke work index were maintained and were often maximal at the lowest PCW achieved. The upright position was well tolerated in patients with normal supine PCW. Normal filling pressures can be achieved in patients with congestive heart failure without compromise of cardiac output. While congestive symptoms should be improved, the feasibility and benefit of maintaining normal filling pressures over a long term must be established.

Penicillin and the marked decrease in morbidity and mortality from rheumatic fever in the United States

There has been a marked decline in mortality due to rheumatic fever in the United States. We present evidence for the important role of penicillin in changing the severity of rheumatic carditis, beginning about 1946. Since that year, mortality due to rheumatic carditis has rapidly decreased to zero at the hospital we studied (House of the Good Samaritan, Boston), the rate of loss of all murmurs in patients at the study hospital accelerated simultaneously and exceeded 40 percent by 1970, and the rates of decline in national mortality due to rheumatic carditis accelerated fourfold with the advent of antibiotics. These data, together with reports of recent outbreaks of rheumatic fever, emphasize the importance of continued efforts to diagnose and treat Group A streptococcal pharyngitis.

Antibiotic prophylaxis against infective endocarditis after normal delivery--is it necessary?

During the years 1959 to 1978 inclusive 2165 women with rheumatic or congenital heart disease had vaginal deliveries at three large Dublin maternity hospitals. There were two (0.09%) cases of puerperal infective endocarditis, neither of which was unequivocally related to preceding childbirth during this period. Routine peripartum antibiotic prophylaxis was not given to either. A questionnaire of the practice of 19 obstetricians in Ireland showed that 12 (63%) gave antibiotics routinely during labour and after delivery in cardiac patients, five (26%) did not, and two (11%) used them occasionally. Peripheral vein blood was drawn serially from 0 to 30 minutes after vaginal delivery to determine the incidence of asymptomatic puerperal bacteraemia. A total of 299 cultures was obtained from 83 normal women and single blood cultures were positive in three women (3.6% of patients, 1.0% of cultures). A review of the published reports showed that well-documented cases of infective endocarditis and of asymptomatic puerperal bacteraemia after normal vaginal delivery are uncommon. There is evidence that antibiotic prophylaxis may increase the risk of developing antibiotic-resistant endocarditis. Recommended prophylactic regimens carry a considerable risk of drug toxicity. These facts, coupled with a lack of direct evidence in support of the efficacy of antibiotic prophylaxis, suggest that routine peripartum antibiotic prophylaxis is not indicated.

Hemodynamic effects of diuresis at rest and during intense upright exercise in patients with impaired cardiac function

Although diuretic therapy appears to improve the exercise capacity of patients with moderately impaired cardiac function, the hemodynamic basis for this improvement is not clear. It is also unknown to what extent the moderate diuresis that often occurs during the first few days of hospitalization contributes to the normal or nearly normal hemodynamic measurements obtained in certain patients with cardiac impairment who are thought clinically to have signs and symptoms of pulmonary congestion. Accordingly, the circulatory response to moderate diuresis resulting in a loss of weight averaging 3.4 kg was investigated in 15 patients with heart disease. At rest in the supine position mean pulmonary arterial wedge pressure fell after diuresis from an average of 24 to 13 mm Hg. Reductions also occurred in mean pulmonary arterial pressure (42 to 26 mm Hg), mean right atrial pressure (9 to 4 mm Hg), and right ventricular end-diastolic pressure (11 to 6 mm Hg). Cardiac output decreased by an average of 20%, mean systemic arterial pressure by 12%, right ventricular stroke work by 44%, and left ventricular stroke work by 25%. Diuresis also caused similar reductions in these values in the sitting position at rest and during mild and intense levels of treadmill exercise. Despite the reductions in cardiac output, all but one of the patients studied achieved substantial clinical improvement from the diuresis. Such improvement probably resulted from the fact that the beneficial effects of lower pulmonary vascular pressures outweighed the deleterious effect of a reduction in cardiac output. Thus, moderate changes in body weight brought about by either fluid retention or fluid loss may result in substantial alterations in circulatory dynamics. These changes, if unrecognized, can lead to considerable confusion when attempts are made to correlate the hemodynamic findings with the degree of cardiac decompensation as judged clinically.

The treatment of rheumatic carditis: a review and meta-analysis

We performed a meta-analysis of the literature on the treatment of established rheumatic carditis to determine if corticosteroid therapy is superior to salicylates in preventing the sequela of inflammation--valvular damage. We identified 22 reports of comparative trials published since the introduction of corticosteroids in 1949. Five of the 22 studies met the criteria we established for the meta-analysis, which included using randomization and a 1-year follow-up for the presence of a new pathologic apical systolic murmur. Based on the meta-analysis, the advantage of corticosteroid treatment over salicylates in preventing a pathologic murmur at 1 year posttreatment is not statistically significant (estimated odds ratio 0.88; 95% confidence interval: 0.53 to 1.46). However, the meta-analysis is dominated by 1 large negative trial, and there was significant heterogeneity in the results obtained from the studies in the meta-analysis; thus, the question of whether corticosteroid therapy is marginally superior to salicylates for the prevention of valvular heart disease from rheumatic fever remains open.

Resistance to medical therapy of gastric ulcers in rheumatic disease patients taking aspirin. A double-blind study with cimetidine and follow-up

Little is known about healing or recurrence of aspirin-induced gastric ulcers if aspirin intake is continued. A double-blind controlled study compared cimetidine plus antacids as needed (prn) with placebo plus prn antacids in healing aspirin-associated gastric ulcers during continued salicylate ingestion in 18 rheumatic disease patients over a 2-month period. Healing occurred in 44% of the placebo and 56% of the cimetidine-treated patients (P greater than 0.05). Subjects in both groups ingested potentially therapeutic doses of antacid. Ulcer size had an effect on healing rate, irrespective of treatment. Ninety percent of gastric ulcers less than 0.5 cm in diameter healed in 2 months but only 25% of ulcers greater than 0.5 cm. Six of seven patients with unhealed ulcers at 2 months eventually healed medically at intervals of 6--26 months. Of 11 patients managed medically and followed endoscopically for a mean of 15 months after healing, only one had a recurrent ulcer. In conclusion, placebo and antacid therapy were as effective as cimetidine and antacids in healing ulcers over a 2-month period. In spite of continued aspirin intake, most benign gastric ulcers less than 0.5 cm in diameter heal medically in two months. Aspirin-induced ulcers greater than or equal to 1 cm in diameter are relatively resistant to therapy but can be healed with prolonged cimetidine and antacid treatment; once healed, recurrence rate is low with prophylactic therapy even with continued aspirin intake.

Penicillin-resistant oral streptococci

The tubular handling of gentamicin (G) and its intrarenal distribution were determined to elucidate the mechanism of G accumulation in the kidney. At a serum level of 11.1 ± 0.5 μg/ml (10 animals), as maintained by constant infusion for 5 h, serum Na⁺ and K⁺, arterial pressure, effective renal plasma flow and glomerular filtration rate remained undisturbed. The clearance values in milliliters per minute for G, inulin, and p-aminohippuric acid were 40.3 ± 1.8, 49.9 ± 2.8, and 132 ± 14, respectively. The ratio of clearance of G to clearance of inulin was 0.82 ± 0.04 (P < 0.005), suggesting net reabsorption of G by the renal tubules. The renal cortex/serum ratio for G was 11.9 ± 2.1, and the medulla/serum ratio was 2.7 ± 0.4, indicating greater uptake of G by the cortex. The extraction ratio of p-aminohippuric acid was 0.74 ± 0.03. In contrast, the extraction ratio of G was 0.20 ± 0.03, which was significantly lower than that of inulin (0.30 ± 0.04). It is concluded that the accumulation of G in the cortex was due to tubular reabsorption. Probably some of the reabsorbed G became trapped in the epithelial cells after crossing the luminal membrane, whereas some returned to the circulation.

Significance of His and left bundle recordings from the left heart in man

Eight patients were studied by simultaneous intracardiac recordings of the specialized conduction system from left and right heart. Five patients had normal A-V conduction, one had left axis deviation (LAD), and two had bundle-branch block. Bundle of His (BH) and right bundle (RB) recordings from the right heart were obtained and validated as previously described. In addition a bipolar electrode catheter was introduced into the root of the aorta and left ventricle via the right brachial artery. BH and left bundle (LB) electrograms were recorded at the level of the aortic cusps and just below the aortic valve, respectively. BH recordings from both sides could be temporally superimposed and were similar in onset and duration. In patients with normal A-V conduction the duration of these deflections was BH 15 to 20, LB 15, and RB 10 msec. The conduction time from the proximal LB to ventricular (V) activation (LB-V) ranged from 20 to 25 msec. The LB-V and RB-V conduction times from comparable points were similar and support the previous observations that interventricular septal activation occurs almost simultaneously on both sides. In the patient with right bundle-branch block (RBBB) and LAD with a slightly prolonged H-V time (50 msec), the delay was localized distal to the main LB (LB-V = 30 msec). During ectopic "ventricular," probably left bundle rhythm, retrograde activation of the BH was demonstrated. Aberration (RBBB) of the supraventricular impulse resulting from invasion of the RB by the preceding interpolated premature "ventricular" beat is suggested.

Latent Rheumatic Heart Disease: Identifying the Children at Highest Risk of Unfavorable Outcome

BACKGROUND

Screening echocardiography has emerged as a potentially powerful tool for early diagnosis of rheumatic heart disease (RHD). The utility of screening echocardiography hinges on the rate of RHD progression and the ability of penicillin prophylaxis to improve outcome. We report the longitudinal outcomes of a cohort of children with latent RHD and identify risk factors for unfavorable outcomes.

METHODS

This was a prospective natural history study conducted under the Ugandan RHD registry. Children with latent RHD and ≥1 year of follow-up were included. All echocardiograms were re-reviewed by experts (2012 World Heart Federation criteria) for inclusion and evidence of change. Bi- and multivariable logistic regression, Kaplan-Meier analysis, and Cox proportional hazards models, as well, were developed to search for risk factors for unfavorable outcome and compare progression-free survival between those treated and not treated with penicillin. Propensity and other matching methods with sensitivity analysis were implemented for the evaluation of the penicillin effect.

RESULTS

Blinded review confirmed 227 cases of latent RHD: 164 borderline and 63 definite (42 mild, 21 moderate/severe). Median age at diagnosis was 12 years and median follow-up was 2.3 years (interquartile range, 2.0-2.9). Penicillin prophylaxis was prescribed in 49.3% with overall adherence of 84.7%. Of children with moderate-to-severe definite RHD, 47.6% had echocardiographic progression (including 2 deaths), and 9.5% had echocardiographic regression. Children with mild definite and borderline RHD showed 26% and 9.8% echocardiographic progression and 45.2% and 46.3% echocardiographic improvement, respectively. Of those with mild definite RHD or borderline RHD, more advanced disease category, younger age, and morphological mitral valve features were risk factors for an unfavorable outcome.

CONCLUSIONS

Latent RHD is a heterogeneous diagnosis with variable disease outcomes. Children with moderate to severe latent RHD have poor outcomes. Children with both borderline and mild definite RHD are at substantial risk of progression. Although long-term outcome remains unclear, the initial change in latent RHD may be evident during the first 1 to 2 years following diagnosis. Natural history data are inherently limited, and a randomized clinical trial is needed to definitively determine the impact of penicillin prophylaxis on the trajectory of latent RHD.

The natural history of rheumatic fever and rheumatic heart disease. Ten-year report of a cooperative clinical trial of ACTH, cortisone, and aspirin

1. A study has been made 10 years after the end of treatment of the 497 children who were admitted to the U.K./U.S. cooperative clinical trial of the relative merits of ACTH, cortisone, and aspirin in the treatment of acute rheumatic fever.

2. Three hundred and ninety-seven of the cases (79.9 per cent) were known to be alive at 10 years and the status of the heart was known for 347 of them. In addition, 23 (4.6 per cent) had died, 19 from rheumatic fever and rheumatic heart disease, and 77 (15.5 per cent) were untraced. The very low fatality rate is striking.

3. At the end of 10 years, there is no evidence that, on the treatment schedule used in this study, the prognosis has been influenced more by one treatment than another. This confirms the findings reported at 1 year and at 5 years.

4. The most important factor in determining the prevalance of rheumatic heart disease at the end of 10 years is the status of the heart at the time treatment was begun. For cases initially without carditis the prognosis was excellent, since in 94 per cent there was no residual heart disease.

In cases initially with carditis but without pre-existing heart disease, the proportion without residual heart disease was 70 per cent for those with only a grade I apical systolic murmur, and 74 per cent for those with only a grade II or III apical systolic murmur. The proportion without heart disease decreased to 32 per cent for those initially with failure and/or pericarditis.

In cases with pre-existing heart disease, the prognosis was poor. Forty per cent of those initially without pericarditis or failure and only 11 per cent of those with pericarditis and/or failure were without heart disease at 10 years.

5. Mitral stenosis, uncommon at 5 years, was definitely diagnosed in 18 of the 347 cases examined at 10 years and in 7 of the 19 deaths from rheumatic fever and rheumatic heart disease. The prevalence of this complication increased with the severity of the cardiac status at start of treatment and was greater in females than in males.

6. Retreated recurrences of rheumatic fever in cases without pre-existing heart disease worsened the prognosis but did not increase the prevalence of mitral stenosis. Patients surviving an initial attack of rheumatic fever without residual heart disease do develop heart disease following a retreated recurrence. The effect of initial cardiac status on, the recurrence rate could not be determined.

7. Sex affected the outcome at 10 years. Rheumatic fever in its milder grades had a worse prognosis, and mitral stenosis was more common in females than in males.

8. These results make clear that the status of the heart of the patients at the start of treatment, the rate of recurrence of acute rheumatic fever, and the sex of the subjects must all be taken closely into account in the evaluation of any treatment of acute rheumatic fever.

The INVICTUS rheumatic heart disease research program: Rationale, design and baseline characteristics of a randomized trial of rivaroxaban compared to vitamin K antagonists in rheumatic valvular disease and atrial fibrillation

BACKGROUND

Rheumatic heart disease (RHD) is a neglected disease affecting 33 million people, mainly in low and middle income countries. Yet very few large trials or registries have been conducted in this population. The INVICTUS program of research in RHD consists of a randomized-controlled trial (RCT) of 4500 patients comparing rivaroxaban with vitamin K antagonists (VKA) in patients with RHD and atrial fibrillation (AF), a registry of 17,000 patients to document the contemporary clinical course of patients with RHD, including a focused sub-study on pregnant women with RHD within the registry. This paper describes the rationale, design, organization and baseline characteristics of the RCT and a summary of the design of the registry and its sub-study. Patients with RHD and AF are considered to be at high risk of embolic strokes, and oral anticoagulation with VKAs is recommended for stroke prevention. But the quality of anticoagulation with VKA is poor in developing countries. A drug which does not require monitoring, and which is safe and effective for preventing stroke in patients with valvular AF, would fulfill a major unmet need.

METHODS

The INVestIgation of rheumatiC AF Treatment Using VKAs, rivaroxaban or aspirin Studies (INVICTUS-VKA) trial is an international, multicentre, randomized, open-label, parallel group trial, testing whether rivaroxaban 20 mg given once daily is non-inferior (or superior) to VKA in patients with RHD, AF, and an elevated risk of stroke (mitral stenosis with valve area ≤2 cm2, left atrial spontaneous echo-contrast or thrombus, or a CHA2DS2VASc score ≥2). The primary efficacy outcome is a composite of stroke or systemic embolism and the primary safety outcome is the occurrence of major bleeding. The trial has enrolled 4565 patients from 138 sites in 23 countries from Africa, Asia and South America. The Registry plans to enroll an additional 17,000 patients with RHD and document their treatments, and their clinical course for at least 2 years. The pregnancy sub-study will document the clinical course of pregnant women with RHD.

CONCLUSION

INVICTUS is the largest program of clinical research focused on a neglected cardiovascular disease and will provide new information on the clinical course of patients with RHD, and approaches to anticoagulation in those with concomitant AF.

Haemodynamic effects of glucagon

The central and peripheral vascular haemodynamic effects of glucagon were studied in 29 patients. With a single dose method of 2 or 5 mg. glucagon intravenously the inotropic action of the drug produced immediate increased myocardial contractility with significant increase in cardiac output and enhanced cardiac performance, and lowering of pulmonary arterial pressure and pulmonary vascular resistance. No primary peripheral vascular effect was evident, and the increased systemic pressure and lowered systemic resistance appear to be secondary to the central action of the drug. With the dosage used there were no undesirable side-effects apart from a feeling of slight nausea. Though the haemodynamic effects are abrupt, reaching their maximum values in the first 10 minutes after injection, they tend to be dissipated within half an hour, presumably due to the very rapid destruction of the drug. Repeated booster doses rather than continuous infusion may be the method of choice to maintain an increased cardiac output. The positive chronotropic action of the drug may cause transient palpitations. Glucagon increased the cardiac output in the acute phase of myocardial infarction by 42 per cent. The haemodynamic effects in chronic rheumatic heart disease are more varied, and it may increase left atrial pressure in mitral stenosis, which is undesirable. Hyperglycaemia results from liver glycogenolysis but blood sugar levels rarely exceeded 200 mg./100 ml. These results warrant further study of the value of glucagon as a positive inotropic agent in low output heart failure, especially in acute myocardial infarction with cardiogenic shock, or after cardiac surgery, or in unrelieved chronic congestive heart failure.

Rheumatic fever recurrences: controlled study of 3-week versus 4-week benzathine penicillin prevention programs

To compare the merits of 3-week versus 4-week injections of benzathine penicillin G in preventing recurrence of rheumatic fever, 179 patients aged 4 to 19 years were assigned to one of the two programs. Age, weight, cardiac status, and streptococcal infections among the patients and their family members studied in each program were comparable. Eight-two patients and their family members were monitored for streptococcal infections. Compliance in the two programs was comparable. Of the 63 patients who stayed in the 4-week program, RF recurred in six, as a result of prophylaxis failure in five and associated with partial compliance in one. Of the 90 patients in the 3-week program, RF recurred in one, associated with partial compliance; no failures occurred (P = 0.01). We recommended that for RF chemoprophylaxis in individuals at great risk, regardless of age, benzathine penicillin injections should be administered every 3 rather than every 4 weeks.

Improvement in rheumatic fever and rheumatic heart disease management and prevention using a health centre-based continuous quality improvement approach

BACKGROUND

Rheumatic heart disease (RHD) remains a major health concern for Aboriginal Australians. A key component of RHD control is prevention of recurrent acute rheumatic fever (ARF) using long-term secondary prophylaxis with intramuscular benzathine penicillin (BPG). This is the most important and cost-effective step in RHD control. However, there are significant challenges to effective implementation of secondary prophylaxis programs. This project aimed to increase understanding and improve quality of RHD care through development and implementation of a continuous quality improvement (CQI) strategy.

METHODS

We used a CQI strategy to promote implementation of national best-practice ARF/RHD management guidelines at primary health care level in Indigenous communities of the Northern Territory (NT), Australia, 2008-2010. Participatory action research methods were employed to identify system barriers to delivery of high quality care. This entailed facilitated discussion with primary care staff aided by a system assessment tool (SAT). Participants were encouraged to develop and implement strategies to overcome identified barriers, including better record-keeping, triage systems and strategies for patient follow-up. To assess performance, clinical records were audited at baseline, then annually for two years. Key performance indicators included proportion of people receiving adequate secondary prophylaxis (≥80% of scheduled 4-weekly penicillin injections) and quality of documentation.

RESULTS

Six health centres participated, servicing approximately 154 people with ARF/RHD. Improvements occurred in indicators of service delivery including proportion of people receiving ≥40% of their scheduled BPG (increasing from 81/116 [70%] at baseline to 84/103 [82%] in year three, p = 0.04), proportion of people reviewed by a doctor within the past two years (112/154 [73%] and 134/156 [86%], p = 0.003), and proportion of people who received influenza vaccination (57/154 [37%] to 86/156 [55%], p = 0.001). However, the proportion receiving ≥80% of scheduled BPG did not change. Documentation in medical files improved: ARF episode documentation increased from 31/55 (56%) to 50/62 (81%) (p = 0.004), and RHD risk category documentation from 87/154 (56%) to 103/145 (76%) (p < 0.001). Large differences in performance were noted between health centres, reflected to some extent in SAT scores.

CONCLUSIONS

A CQI process using a systems approach and participatory action research methodology can significantly improve delivery of ARF/RHD care.