Cardiac Society of Australia and New Zealand position statement executive summary: coronary artery calcium scoring.

Introduction This article summarises the Cardiac Society of Australia and New Zealand position statement on coronary artery calcium (CAC) scoring. CAC scoring is a non-invasive method for quantifying coronary artery calcification using computed tomography. It is a marker of atherosclerotic plaque burden and the strongest independent predictor of future myocardial infarction and mortality. CAC scoring provides incremental risk information beyond traditional risk calculators such as the Framingham Risk Score. Its use for risk stratification is confined to primary prevention of cardiovascular events, and can be considered as individualised coronary risk scoring for intermediate risk patients, allowing reclassification to low or high risk based on the score. Medical practitioners should carefully counsel patients before CAC testing, which should only be undertaken if an alteration in therapy, including embarking on pharmacotherapy, is being considered based on the test result. Main recommendations CAC scoring should primarily be performed on individuals without coronary disease aged 45-75 years (absolute 5-year cardiovascular risk of 10-15%) who are asymptomatic. CAC scoring is also reasonable in lower risk groups (absolute 5-year cardiovascular risk, < 10%) where risk scores traditionally underestimate risk (eg, family history of premature CVD) and in patients with diabetes aged 40-60 years. We recommend aspirin and a high efficacy statin in high risk patients, defined as those with a CAC score ≥ 400, or a CAC score of 100-399 and above the 75th percentile for age and sex. It is reasonable to treat patients with CAC scores ≥ 100 with aspirin and a statin. It is reasonable not to treat asymptomatic patients with a CAC score of zero. Changes in management as a result of this statement Cardiovascular risk is reclassified according to CAC score. High risk patients are treated with a high efficacy statin and aspirin. Very low risk patients (ie, CAC score of zero) do not benefit from treatment.

Early and late results of combined mitral-aortic valve surgery.

OBJECTIVE: This retrospective study was designed to assess the early morbidity and mortality as well as long-term mortality of combined aortic-mitral valve procedures at a single centre. METHODS: Patients were identified by analysing the intensive care and perfusion databases, from 1989 to 2003, with 113 receiving aortic-mitral valve procedures. Eighty-four percent of patients received a mechanical bileaflet valve. Survival was assessed using a Kaplan-Meier method, and determinants of survival with the Cox proportional hazards model. RESULTS: There were 57 men and 56 women, median age 59 (18-84) years. The 30-day mortality was 9% (n=10). This cohort contained a number of high risk patients, 38% were classified as New York Heart Association class IV, 33.5% had at least moderate ventricular impairment, 20% were redo procedures and 17% urgent procedures. Survival estimates at 5 and 10 years were 85% (0.76-0.90) and 65% (0.49-0.77), respectively. Multivariate pre-operative predictors of death included renal dysfunction (creatinine >200 micromol/L) and hypertension. Rheumatic aetiology was associated with improved survival. CONCLUSION: This study shows acceptable short and long-term survival in patients undergoing combined aortic-mitral valve surgical procedures at a single centre. Renal impairment and hypertension were associated with a poorer long-term prognosis and rheumatic aetiology was associated with improved survival. Age, LVEF and NYHA class were not associated with a worse outcome. This may affect future decision making in light of an aging population.

Stress, myocardial infarction, and the "tako-tsubo" phenomenon.

Emotional distress as a trigger for acute myocardial infarction is beginning to gain credibility as it is recognised that traditional risk factors can account for only half of all myocardial infarctions. Here, three cases of myocardial infarction are presented in the setting of an acute emotional stressor, with coronary angiography showing only minimal coronary artery disease. In all cases striking wall motion abnormalities, mimicking a "tako-tsubo", were noted with complete resolution within 30 days. This pattern suggests tako-tsubo-like transient left ventricular dysfunction.

Opening Pandora's box: the unpredictability of reassurance by a normal test result.

OBJECTIVES: To determine the rate of failure of patient reassurance after a normal test result and study the determinants of failure. DESIGN: Replicated single case study with qualitative and quantitative data analysis. SETTING: University teaching hospital. SUBJECTS: 40 consecutive patients referred for echocardiography either because of symptoms (10 patients) or because of a heart murmur (30). 39 were shown to have a normal heart. INTERVENTIONS: Medical consultations and semistructured patient interviews were tape recorded. Structured interviews with consultant cardiologists were recorded in survey form. MAIN OUTCOME MEASURES: Patient recall of the explanation and residual understanding, doubt, and anxiety about the heart after the test and post-test consultation. RESULTS: All 10 patients presenting with symptoms were left with anxiety about the heart despite a normal test result and reassurance by the consultant. Of 28 patients referred because of a murmur but shown to have no heart abnormality, 20 became anxious after detection of the murmur; 11 had residual anxiety despite the normal test result. CONCLUSIONS: Reassurance of the "worried well"-anxious patients with symptoms or patients concerned by a health query resulting from a routine medical examination or from screening-constitutes a large part of medical practice. It seems to be widely assumed that explaining that tests have shown no abnormality is enough to reassure. The results of this study refute this and emphasise the importance of personal and social factors as obstacles to reassurance.

Community exercise to prevent heart disease. How much should we advise?

There is international agreement that those in the community who are habitually active, either in work or in leisure, have a better coronary risk profile and a lower death rate from coronary heart disease (CHD). This agreement is usually translated into recommendations encouraging the population to perform regular aerobic exercise for 30 minutes thrice weekly. Such a policy is intrinsically costly, requiring detailed medical examination, exercise testing and exercise prescription. Such a policy may detect patients with asymptomatic CHD on the basis of silent myocardial ischaemia for whom there is no proven therapy. More often, exercise testing of asymptomatic "well" middle aged populations may well result in a large number of positive tests suggesting the existence of heart disease which is later proven by more expensive testing to be non existent. And finally, only a minority of the population actually exercises aerobically and this proportion falls with the ageing of the population. In summary, such a policy, whilst supported by observational data, is costly and ineffective. Review of the observational studies on physical activity or physical fitness reveals that most, but not all, of the studies show that any level of activity of fitness above basal is protective from CHD--in other words, there appears to be no threshold of activity or fitness for cardiovascular protection. Furthermore, there is a close relationship between the total amount of physical activity performed, the amount of higher intensity aerobic activity performed, and physical fitness. As such, it would appear that we could advise the community to increase the total amount of physical activity to achieve cardiovascular protection.(ABSTRACT TRUNCATED AT 250 WORDS)

The contribution of a non-invasive test to clinical care. The impact of echocardiography on diagnosis, management and patient anxiety.

We prospectively studied the impact of echocardiography on a cardiologist's diagnosis and management plan and on patient anxiety for 300 consecutive referrals. There was an impact on diagnosis in 90% of patients. Most common was confirmation of diagnosis usually with the addition of information pertinent to management (81%); change of disease category or resolution of diagnostic doubt was uncommon (9%). The consultant cardiologist believed the heart to be normal in 48 patients who did not have any associated disease; none had any echocardiographic abnormality. The cardiologist reported increased diagnostic confidence in 74% of all patients but management changed in only 9%. One-third of all patients reported reduced anxiety when this was an important clinical issue but in less than half of them did the cardiologist consider that echocardiographic information was essential for reassurance. Anxiety was increased in 6%, and in 12% the anxiety response was inconsistent with the test result. The clinical contribution of the test report was most obvious for those patients (30%) in whom this data was required for (a) a decision concerning specific diagnostic or technical intervention (b) a change of management plan which implied obvious or likely health benefit (c) reassurance which was a clinically important issue. The magnitude of this contribution was related to the study indication. The value of echocardiography is obvious when assessing patients for invasive intervention or when proper treatment or adequate reassurance are impeded by diagnostic doubt. However, for many current indications, we need better definition of factors which predict a clinically useful result. In particular, when the aim is to rule-out disease, our results suggest that an expert cardiological opinion would often be more appropriate than an echocardiogram.

Prognosis of cardiac disease in the ambulant patient.

Much investigation and treatment in cardiac practice is based on the assumption that unexpected death is common in cardiac patients. The validity of this assumption was examined in 636 of 669 (95.1%) consecutive ambulant patients. During the period from 1978 to 1981, inclusive, 16 (3.9%) of the 407 men (median age, 52 years) and six (2.6%) of the 229 women (median age, 54 years) died. Nineteen of these 22 patients died of cardiac causes; most of these were elderly (average age, 68.5 years), had advanced cardiac disease for many years before their death, and complained of breathlessness at the initial interview. None of these deaths was unexpected. It is concluded that unexpected death is relatively uncommon, even in cardiology practice. The intensive diagnostic and therapeutic regimens directed at younger patients with cardiomyopathy and coronary disease who do not complain of breathlessness are unlikely to have an appreciable impact on mortality.

Technical advances in the investigation of the cardiac patient.

Patients who never have experienced symptoms of heart failure or ischaemia but who demonstrate abnormalities have a much better prognosis than their symptomatic counterparts. At present the significance of some detected abnormalities is unknown: caution in interpreting these is advised and whenever possible an optimistic outlook should be given to the patient.

Assessment of cardiac risk 10 days after uncomplicated myocardial infarction.

A total of 188 patients with uncomplicated acute myocardial infarction (long-term Norris prognostic index 3.2) were rapidly mobilised, underwent a symptom-limited exercise test around the day of discharge from hospital (day 10), and returned to work at a median of six weeks after the acute event. The incidence of cardiac death six months, one year, and three years after infarction was 2.7%, 4.5%, and 7.3% respectively, and the corresponding figures for recurrent heart attacks were 3.4%, 8.2%, and 18.5% respectively. The risk of recurrence of heart attack was predicted by three variables assessed at discharge--namely, a history of classical effort angina (p less than 0.01), radiological heart failure (p less than 0.05), and angina induced by the exercise test (p less than 0.05). The presence of any of these risk factors defined a group of patients with a sevenfold risk of recurrent heart attacks within six months of the initial acute infarct. It is concluded that these risk factors identify a group of patients with a high risk of recurrence early after infarction, in whom vigorous secondary prophylaxis is desirable.

Serial M-mode echocardiography in severe chronic aortic regurgitation.

Thirteen patients with severe chronic aortic regurgitation (mean age 52.5 years) were studied by serial M-mode echocardiography. When first studied, none had breathlessness caused by left ventricular failure (LVF). Nine of these patients remained asymptomatic over a mean period of 4 years, 3 months (no LVF group); the other four patients developed left ventricular failure with dyspnea after a mean interval of 3 years, 11 months (LVF group). For both of these groups, we compared the echocardiographic measurements from the first and last of the serial studies. For the LVF group, end-diastolic left ventricular internal dimension increased 14%, end-systolic dimension increased 35%, fractional shortening decreased 45% and left atrial dimension increased 62%. All of these changes were significant. For the No LVF group, the change in end-diastolic left ventricular internal dimension was not significant, but the 6% increase in end-systolic dimension, 10% reduction in fractional shortening and 25% increase in left atrial size were all statistically significant. Although echocardiography could detect declining left ventricular function in a group of asymptomatic patients with severe chronic aortic regurgitation, the reproducibility of the technique was limited in individual patients. Therefore, serial echocardiographic studies should be interpreted in conjunction with clinical assessment and other investigations.

Echocardiographic assessment of cardiac chamber size and left ventricular function in aerobically trained athletes.

We compared the echocardiographic assessment of left ventricular function in 20 aerobically trained male athletes (VO2 max 61 ml/kg/min) with 20 control subjects of similar age and size (VO2 max 37 ml/kg/min). On average, the left ventricle was larger in athletes and the extent of myocardial contraction (fractional shortening) was reduced. In nine athletes, fractional shortening was less than our laboratory lower limit of normal (26%) and in four athletes the left ventricle was enlarged and fractional shortening was reduced. However, the peak rate of circumferential shortening was not reduced in athletes. We concluded that athletes have normal myocardial contractility but some have a reduced extent of myocardial contraction which could be mistaken for the effects of myocardial disease.

History, exercise test, and prognosis of chest pain.

Three hundred and eighteen patients were followed up for periods up to seven years (mean, 37.5 months) after an initial assessment of their history followed by a symptom-limited exercise test. Twenty-four of the subjects (7.6%) died, eight within one month of being seen within the unit. The major determinant of mortality was the presence and severity of effort angina. Thus, the survival rates of patients with severe angina, mild angina, and atypical pain were 86.8%, 97.6%, and 99.5% at one month and 73%, 82%, and 93% at five years respectively. The occurrence of angina or ST-segment depression, reduced working capacity, and peak heart rate on exercise testing were all associated with an increased risk of premature mortality. However, the exercise testing abnormalities were closely correlated with the presence and severity of angina by history, except in patients with atypical histories. The major contribution of exercise tests is to the patients with atypical, but possibly eschaemic, chest pains.

Shortened cardiac rehabilitation: a three year experience.

One-hundred-and-twenty-four (19%) of patients with acute myocardial infarction seen in a three year period from 1975 to 1978 were considered low risk patients suitable for rapid mobilisation, early discharge, and early exercise testing. Their mean long term Norris Prognostic Index was 3.2; the mean date of discharge was 9.6 days, and the mean date of exercise testing was 10.5 days. There were seven deaths and nine non-fatal recurrent myocardial infarctions in a mean follow up time of 14.2 months. These events were best predicted by a history of angina prior to myocardial infarction or radiological cardiomegaly detected in the CCU. Altogether 98 (80%) of the patients returned to work at a median time of six weeks after their infarct. The nett effect of the team activity has been to reduce the need for referral to the National Heart Foundation Assessment Centre from an average of 15 patients per year to an average of two per year.

Exercise induced arrhythmias: their implications for cardiac rehabilitation programs.

The exercise induced frequent ventricular premature beat (VPB) usually indicates the presence of frequent and complex forms of VPB on 24-hr ambulatory monitoring. While it is commonly associated with coronary heart disease (CHD) with abnormalities of left ventricular contraction (LVC) it is not specific for this condition. In the context of CHD with LVC, frequent or complex VPB substantially increase the risk of sudden cardiac death. No therapy is known to reliably suppress VPB and thereby prevent sudden death.

The significance of chest pain occurring with the Master two step test.

This study has assessed whether chest pain occurring during or after a step test could improve the accuracy of exercise testing in the diagnosis of coronary artery disease (CAD). One hundred and fifty-three consecutive men underwent the double Master two-step test prior to diagnostic coronary arteriography. On hundred and twenty-five had CAD, 28 insignificant disease (NCA). The post-exercise ECG showed at least 0-5 mm of ischaemic ST depression in 71 (57%) of the men with CAD and in five (18%) with NCA. Ischaemic ST depression of at least 2-0 mm occurred in 24 men, all of whom had CAD. Chest pain occurred during or after the test in 78 (62%) men with CAD and in nine (33%) with NCA. The accuracy of diagnosis of CAD could be improved by combining the occurrence of chest pain in the test with a positive post-exercise ECG. Either a 2 mm positive post-exercise ECG with or without test angina or 0-5 mm to 1-9 mm positive post-exercise ECG with test angina was found in 56 (45%) of men with CAD and one (4%) with NCA. Thus the concurrence of chest pain during or after a double Master two-step test, together with ischaemic ST segment depression after the test, strongly suggests the presence of CAD.