Sunday, May 6, 2007

Clinical innovation, prevention - On Preventing Heart and Lung Disease at Same Time

My Occasional Clinical Innovation Blog

Innovation as a “Why Not Game.” Why Not Prevent Heart and Lung Disease Before The Horses are Out of the Barn? Why Not Pack in Cigarettes Before Pack-Years, Pulmonary, and Coronary Pipe Pathologies Pile Up?

Chest pain is the second most common reason for a patient to visit the emergency room (abdominal pain is number one. Each year in the United States and Canada there are more than six million evaluations in the ER of patients. But despite its frequency, chest pain is one of the most challenging symptoms for the clinician to unravel.

Jerome Groopman, MD, How Doctors Think, Houghton Mifflin Company, 2007

CPOD is generally a silent and unknown killer.

Lung Association, 2007

Occasionally a clinical innovation becomes an exercise in asking “Why not/”

• Why not detect early heart and lung disease at same time?
• Why not modify existing technologies that have been around for decades – coronary stress tests and tests to measure lung function – into one machine to do the jobs simultaneously?
• Why not kill two birds – coronary artery disease and chronic obstructive lung disease – two of the biggest killers of Americans – with one stone, a device for picking up early signs of both at one setting?
• Why not pack in those cigarettes before those pack-years add up while the packing is good?

These questions sprang to mind when reading Two May 2 Wall Street Journal pieces, “Heart Scanners Gain Popularity” and “Shining Light on a Deadly Lung Disorder.”

The first piece concerned heart scanners as precise devices for spotting coronary disease, and the second, highlighted chronic obstructive lung disease (COPD) as a deadly ailment afflicting 24 million Americans.

Smoking commonly causes coronary disease and COPD.


The four most common causes of death in the United States are:

1. Diseases of the heart, mostly from coronary artery disease; the risk goes up with smoking
2. All cancers, of which lung cancer is the most common
3. Stroke, the risk rises with smoking
4. Chronic obstructive lung disease, most often the consequence of smoking

The four most common causes of preventable death are:

1. Smoking
2. Poor diet and physical inactivity
3. Alcohol consumption
4. Infections

In short, smoking, coronary disease, and COPD are closely connected. That’s why heart scanners and spirometers are good for detecting these diseases but are too late in game to prevent them.

• The promise and purpose of heart scanners is that these scanners can expose coronary artery disease as the culprit producing chest pain within 10 to 15 minutes. This speed and precision makes scanners invaluable in emergency room settings. Speed and accuracy saves lives and expense and avoids risks of stress tests and invasive angiography. The cost of a coronary workup – cardiac enzymes, ECG, stress tests, and angiography- are the core of an industry generating $10 to $12 billion in revenues, as compared to about $2 billion for scanners. “Because stress tests are not perfect, there are many patients who go to the cath lab who don’t need it,” says Dr. Harvey Hecht, chief of computer tomography at Lennox Hill Hospital in Manhattan,”All of these will be eliminated by doing cardiac CT.”

• COPD is an umbrella term for lung diseases that inflame airways, obstruct breathing, trap bad air in lungs. COPD includes emphysema and chronic bronchitis. COPD produces coughing, wheezing, shortness of breath, excess sputum, and inability to breath or take a deep breath. Many COPD sufferers become lung cripples, confined to wheelchairs and tethered to oxygen tanks. Most COPD patients are present or past smokers The gold standard for diagnosing COPD is spirometry. Hand-held spirometers are in the offices of about 40% of primary care physicians, but are too infrequently used on two few patients. These spirometers are useful, but should be more widely deployed to detect the 12 million people with COPD who are not aware they have the disease.

Pack Years

This brings me to “pack years,” a useful concept for smokers to ponder before continuing to smoke. “Pack years” measures the total impact of smoking has person has incurred through smoking over the years. Calculate it by multiplying the number of packs smoked per day by the number of years smoked. If you’ve smoked two packs a day for 20 years, that’s 40 pack years. Get above 10 pack years, and you’re likely to be a future heart disease, COPD, or lung cancer victim.

Pack Years in Heart and Lung Disease

Heavy smoking (more than 30 pack years) is common in coronary disease. Pack years of 30 or more are also directly related with COPD and lung cancer. If you’ve smoked one pack a day from age 20 to 50, you have 30 pack years. Two packs a day would be 60 pack years.

Pack years add up and their damage never completely goes away, even after you stop. Age may not count. I once saw a 26 year man who died of lung cancer. He had smoked 4 packs a day since he was 12 and had 56 pack years under his sternum. Hospital wards, at the VA and elsewhere are full of older men, sometimes called“chronic lungers,” individuals suffering damage from excessive pack years.

A Device for Simultaneously Evaluating Heart and Lung Function

What would be ideal to ward off heart and disease from smoking would be a device measuring early heart and lung damage at the same time. Such a device, called SHAPE (Superior Heart and Pulmonary Evaluation) has been developed by entrepreneurs in partnership with the Mayo Clinic.

SHAPE consists of :

• A one-step staircase instead of the traditional treadmill (after one to two steps up the staircase, one can amplify the ECG signals to detect damage from coronary disease without the risk of driving the subject to exhaustion and the risk of having an arrhythmia or death while on the treadmill);
• a scuba-like mouthpiece hooked to a gas analyzer (this detects the efficiency of carbon dioxide and oxygen exchange, which is decreased in COPD and sometimes in heart disease as well);
• a laptop computer (It contains a large database of patients with coronary disease and/or COPD and allows one to predict chances of hospitalization and/or death).

This device, is not yet on the market, but it has been tested and validated by the Mayo Clinic. It is smaller and less expensive than the treadmill machine now used. The traditional treadmill is of no help in evaluating lung function. SHAPE , on the other hand,m may deter patients from further smoking by revealing heart and lung damage. . SHAPE can detect an early decline in coronary/pulmonary fitness or damage from smoking.

Imagine a 40 year old asymptomatic executive, with 20 pack years behind him, who suddenly finds he has early heart or lung damage and may be a future candidate for hospitalization, even death. That piece of news constitute an instant smoker-stopper.

To smokers, early concrete evidence of damage from their addiction is likely to be credible evidence to induce them to stop before too many more pack years elapse.


1. Henry Sanderson, “Heart Scanners Gain Popularity,” Wall Street Journal, May 2, 2007.
2. Laura Landro, “Shining a Light on a Deadly Lung Disorder,” Wall Street Journal, May 2, 2007.

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