Dr K K Aggarwal

Guidelines out for diagnostic cath use

The explosion of advanced cardiovascular diagnostic technology has prompted the publication of the first-ever appropriate use criteria for diagnostic catheterization.

Out of a possible 166 clinical scenarios for the use of diagnostic cath, a panel of experts identified nearly half as appropriate, 30% as uncertain, and 25% as inappropriate, according to Manesh Patel, MD, from Duke University, and colleagues. The document will be published in the May 29 issue of the Journal of the American College of Cardiology and also will be co-published in Catheterization and Cardiovascular Interventions and the Journal of Thoracic and Cardiovascular Surgery.

A few examples where the technical panel determined that diagnostic cardiac catheterization was appropriate include patients:

• Without prior stress testing but who report symptoms and have a high pretest probability, or high likelihood of disease in the physician’s judgment
• With definite or suspected acute coronary syndrome
• With typical symptoms and intermediate- or high-risk findings on prior diagnostic testing
• With suspected pulmonary hypertension with equivocal or borderline elevated estimated right ventricular systolic pressure on resting echo

Examples of where the panel determined a diagnostic cath to be inappropriate include:

• Asymptomatic patients at low or intermediate risk for coronary artery disease without a prior stress test
• As part of a preoperative work up for noncardiac surgery in patients with good functional or exercise capacity
• In mild, moderate, or severe mitral stenosis or regurgitation when noninvasive imaging is concordant with the clinical impression of severity
• In patients with syncope and low risk of heart disease and in patients with new-onset atrial fibrillation or flutter with low or intermediate coronary heart disease risk.

A few examples of tests the panel deemed uncertain include those in:

• Asymptomatic patients with a high global coronary artery disease risk and no prior stress test
• Symptomatic patients with an intermediate pretest probability and no prior stress test
• Asymptomatic patients whose imaging stress test showed intermediate risk (however, the test is appropriate in symptomatic patients whose stress test shows intermediate risk)
• Suspected arrhythmogenic right ventricular dysplasia

A diagnostic cath is inappropriate in asymptomatic patients no matter what their coronary artery calcium score is. No grades were given for symptomatic patients because coronary artery calcium scans are inappropriate in these patients.

In symptomatic patients who have undergone coronary CT angiography, a diagnostic cath is appropriate when the imaging shows:

• A non-left main or left main lesion greater than 50% stenosed or lesions of the same severity in more than one coronary branch
• A lesion of unclear severity, possibly obstructive, left main or non-left main

However, it is of uncertain appropriateness when the non-left main lesion is less than 50% blocked and when a similarly blocked lesion has extensive partly calcified and non-calcified plaque. The use of fractional flow reserve or intravascular ultrasound in conjunction with an appropriate diagnostic cath is generally inappropriate when non-obstructive lesions are less than 50% blocked, or when the lesions are greater than 70% stenosed and prior testing has agreed with ischemic findings.

AUC for diagnostic cath should be used with the AUC for coronary revascularization. They also suggested that decision support and educational tools be developed around the two sets of criteria.

These criteria were developed by American College of Cardiology and the Society for Cardiovascular Angiography and Interventions in collaboration with the American Association for Thoracic Surgery, the American Heart Association, the American Society of Echocardiography, the American Society of Nuclear Cardiology, the Heart Failure Society of America, the Heart Rhythm Society, the Society of Critical Care Medicine, the Society of Cardiovascular Computed Tomography, the Society for Cardiovascular Magnetic Resonance and the Society of Thoracic Surgeons.

Aishwarya’s weight gain

Aishwarya has been in the news again post delivery. She has gained a lot of weight. It has become a topic for discussion in the social media.

Physiological changes relating to pregnancy result in weight gain in the absence of pathological water retention.  Excessive weight gain causes increase in fat stores. Post partum weight retention is a problem for a large proportion of mothers even at one year after the birth.

Women with high BMI have the highest risk of excessive weight gain and postpartum maternal weight retention, which can be associated with lifelong medical complications.

Women with BMI> 25 should not gain more than 11.5 kg during pregnancy and with BMI > 30 should not be allowed more than 9 kg of weight gain during pregnancy. These women should receive thorough counseling regarding risk of obesity in and out of pregnancy and they should be counseled for proper weight gain and weight loss in the postpartum period. For women with BMI > 35, one should try for either a small weight loss or maintenance of weight during pregnancy.

Weight gain in pregnancy involves the following:

• Fat stores: 2.7 to 3.6 kg
• Increased blood formation: 1.3 to 1.8 kg
• Increased fluid formation: 0.9 to 1.3 kg
• Breast enlargement: 0.9 to 1.3  kg
• Uterine placenta : 0.9 kg

It is evident that weight gain in the postpartum period invariably means gain in fat, which is dependent on lifestyle and dietary habits. Women, therefore, should be counseled during pregnancy so that they do not continue gaining weight after the pregnancy.

Progesterone levels during pregnancy are responsible for fat accumulation during first and second trimesters and for fat mobilization during third trimester. Leptin levels correlate positively with body fat content and BMI, increase during pregnancy and play a direct role in pregnancy-related weight gain and postpartum weight retention.

The benefits of napping

With age come changes in the structure and quality of our sleep. After about age 60, we have less deep (slow-wave) sleep and more rapid sleep cycles, we awaken more often, and we sleep an average of two hours less at night than we did as young adults. It was once thought that older people didn’t need as much sleep as younger ones, but experts now agree that’s not the case. Regardless of age, we typically need seven-and-a-half to eight hours of sleep to function at our best. So if you’re not getting enough sleep at night, what about daytime naps? Or does napping disrupt the sleep cycle, ultimately yielding less sleep and more daytime drowsiness?

These questions were addressed in a recent study by researchers at the Weill Cornell Medical College in White Plains, N.Y., and published in the Journal of the American Geriatrics Society (February 2011). The authors concluded that napping not only increases older individuals’ total sleep time—without producing daytime drowsiness—but also provides measurable cognitive benefits.

This small but well-designed study involved 22 healthy women and men ages 50 to 83 who agreed to be evaluated in a sleep laboratory. During a one- to two-week preliminary period, participants kept sleep logs at home and wore monitors to track their nighttime movements. They were then brought into the sleep laboratory for three nights and two days and given a thorough sleep evaluation (using polysomnography and other techniques) and a battery of cognitive tests. After this initial laboratory session, participants started a month-long daily napping routine at home: half took short (45-minute) naps, and half took longer (two-hour) naps. After the second and fourth weeks, all returned to the lab for repeat assessments.

By study’s end, total sleep time had increased by an average of 65 minutes in the participants assigned to two-hour naps, and by an average of 20 minutes in those assigned to 45-minute naps. Participants found it harder to adhere to the two-hour nap schedule, but neither long naps nor short naps disrupted nighttime sleep or led to daytime sleepiness. Napping increased the time spent in slow-wave and rapid-eye-movement (REM) sleep, which are thought to play important roles in restoring the body and brain. Whether they took long naps or short naps, participants showed significant improvement on three of the four tests in the study’s cognitive-assessment battery.

Only people in good physical and mental health were included in the study, so it’s unclear whether a 45-minute or two-hour napping regimen would be as helpful to older adults with sleep disorders or medical conditions. The study tells us nothing about the effects of shorter naps (for example, so-called power naps) on waking function. Moreover, the study was brief: napping-related cognitive function was measured after only two weeks and four weeks. Whether the improvements observed during the study would continue during subsequent weeks of napping is not known. Nevertheless, the findings provide further evidence that for older people, a daily nap can add to total sleep (as well as time in restorative sleep) and improve daytime function.

[Source: Harvard Healthbeat, reproduced for the benefits of doctors]