The clinical differentiation between cardiac and pulmonary diseases

PULMONARY AND CAKDDOVASC:UT,AK SYSTEMS

The Clinical Differentiation between Cardiac and Pulmonary Diseases PAUL D. WHITE,

T and

M.D.,

cIinica1 differentiation between cardiac pulmonary diseases, aIthough very important, is often difficult because of certain basic facts. In the first pIace, it is not uncommon to Iind both heart and Iungs coincidentaIIy affected in the same individua1, especially at older ages. A common exampIe of this is the Iinding in oId men who are both breathIess, because of chronic bronchitis and pulmonary emphysema, and bothered by angina pectoris due to coronary heart disease; or their breathIessness may be in part due to emphysema and in part to weakness of the Ieft ventricIe secondary to caIcareous aortic stenosis. Not infrequently it is d&uIt to caIcuIate the reIative responsibilities of heart disease and of pulmonary disease in the production of symptoms and signs. More wiI1 be said about that later, but perhaps the most significant point is to remember that both organs can be affected simuItaneousIy. It is aIs of great importance to recognize that disease of one organ, heart or Iung, may be responsibIe for disease of the other. Thus serious chronic fibrosis of the Iung, as in the case of silicosis or of puImonary arteria1 obstruction from massive pulmonary embolism, acute or chronic, or from endarteritis obIiterans, may produce acute or chronic car pulmonale with its enlarged right ventricIe. Similarly, severe mitra1 stenosis, Ieft ventricular failure of long-standing, and constrictive pericarditis invoIving chiefly the Ieft heart chambers can produce so much puImonary hypertension that puImonary arterioscIerosis follows. Indeed, a considerable degree of pulmonary arterioscIerosis secondary to these conditions may in turn have its own effect on HE

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the right ventricle producing some degree of the car pulmonale. Another important consideration is that in the presence of disease of one of the organs, heart or Iungs, the onset or increase of disease of the other may aggravate symptoms and signs due to disease of the former without being the cause of that origina disease. Thus coronary heart disease may be severely aggravated by puImonary emboIism, pneumonia, Iung abscess or pleura1 effusion with exacerbation of angina pectoris, or even the precipitation of coronary thrombosis with or without myocardia1 infarction. Similarly, the disability due to chronic bronchitis with emphysema or to pulmonary emboIism mav be made much worse by the presence of mitral stenosis or Ieft ventricuIar failure or acute coronary thrombosis. AIso, it shouId be emphasized that now and then symptoms and signs of diseases of both organs, heart and Iungs, may be precipitated or aggravated by diseases somewhere eIse in the body, such as acute cholecystitis or a cerebra1 vascular accident, which, however, do not themseIves cause heart disease. The fina basic consideration is that neither heart disease nor pulmonary disease may be present to explain symptoms that are ordinarily attributed to either or both of these conditions. Physiologic factors or extrathoracic conditions may cause reactions in norma heart and lungs that can sometimes be misleading. One of the most common examples of this is that of neurocirculatory asthenia, the cause of which is not clear but which constitutes a definite entity comprising a group of symptoms, in particular dyspnea, often of the sighing variety,

Cardiac and Pulmonary chest pain more where, palpitation

often precordial and faintness.

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practicaIIy of normal size but invariably thcrc wiI1 be some enIargement of the left auricle, which shouId be carefully Iooked for. Cheyne-Stokes dyspnea, that is, alternating apnea and hyperpnea, is to be attributed to cerebral vascuIar insuffIciency, no matter what the cause. Sometimes the heart is partly responsibIe for this because of an inadequate output of bIood, but more often there is cerebra1 vascular disease or serious renaI invoIvement. Pain is the next symptom of importance in the cIinica1 differentiation of cardiac and pulmonary diseases. AIthough there may be deepseated pain or oppression in the Iungs as in the case of some instances of maIignant disease or puImonary emboIism, due in the Iatter case probabIy to dilatation of the pulmonary artery, pain, except for its invoIvement of the pleura, is not a common symptom of diseases of the lungs. PIeuraI pain is quite easiIy differentiated from cardiac pain except when there is pleuropericarditis. Such pain is aggravated by breathing in contrast to cardiac pain which is not. Angina pectoris and the pain of coronary thrombosis are too easily diagnostic to require discussion in this reIationship. On the other hand, the heartache of neurocircuIatory asthenia or pain in or superficia1 to the chest cage from trauma or bursitis, the discomfort of herpes zoster, and “cardiospasm ” are of course to be differentiated from the pains due to either heart or Iung disease; this is usuaIIy done with ease. Cardiospasm is the most common of a11 the disagreeabIe sensations induced substernaIIy, usually with gaseous eructation, by the occurrence of spasm of the esophagus or upper end of the stomach. Cough is rareIy due to heart disease but is very commonly caused by pulmonary disease. There are, however, two cardiac conditions which may give rise to cough in rare cases. One of these is mitra1 stenosis which may resuIt in such enIargement of the heart with displacement and pressure against the bronchi and trachea that cough is sometimes eIicited. The other cardiac condition is congestive faiIure secondary to Ieft ventricuIar weakness resuIting from the strain of chronic hypertension, myocardial infarction or aortic vaIve disease. UsuaIIy it is easy to discover the presence of these cardiac factors. Now and then, of course, both heart and Iung diseases may be causes of cough in the same patient. Hoarseness, Iike cough, is preponderantIy the

SYMPTOMS

In the cIinica1 differentiation of cardiac and puImonary diseases it wiI1 be of interest and vaIue to discuss symptoms that may be independently associated with either heart or Iung disease. The most prominent of these symptoms which may cause confusion is that of d_yspnea. Shortness of breath is one of the chief symptoms of heart disease but it is aIso one of the chief symptoms of Iung disease. UntiI the end of the seventeenth century shortness of breath was ordinarily ascribed to Iung disease. That was before the institution of postmortem examinations. Quite suddenly it was discovered that a person might die with severe dyspnea and have reIativeIy norma Iungs but a very Iarge heart (Bonetus, 1679). There are many pulmonary diseases that cause shortness of breath, both acute and chronic; they are IargeIy of an infectious nature although happiIy such infections are becoming steadiIy rarer. Pneumonia, extensive tubercuIosis, influenza, maIignant disease, pIeurisy with large effusions, pneumoconiosis and puImonary embolism are the more important diseases of the Iungs responsibIe for dyspnea. The two most important cardiac conditions causing dyspnea are: (I) more common, faiIure of the left ventricIe resuIting in congestion of the Iungs; and (2) Iess often, mitra1 stenosis. It is generaIIy quite easy to diagnose these two cardiac conditions and to differentiate them from pulmonary disease. Another important cause of dyspnea is the occurrence of a large pericardia1 effusion. Once in a whiIe, as aIready stated, both heart disease and puImonary disease are present in the same person and may both share the responsibility for dyspnea. In such a case in which Ieft ventricular weakness is a possibIe factor it is wise to give digitaIis as a therapeutic test; often there is a gratifying response with considerabIe decrease of the dyspnea. A very important cIue to exonerate the heart as a cause of dyspnea is x-ray evidence of its norma size. If there is no enIargement of the Ieft ventricIe and no enIargement of the Ieft auricIe, both of these conditions, that is, Ieft ventricuIar faiIure and mitra1 stenosis, can be pretty cIearIy ruIed out. Once in a great while the heart in genera1 in mitra1 stenosis may be 242

Cardiac and Pulmonary result of involvement of the respiratory tract. In very rare cases it is secondary to advanced mitra1 stenosis or pressure from an aneurysm of the thoracic aorta which may result in IaryngeaI paralysis. Hemopt~yysis is aIso rareIy due to heart disease. Like cough, it can resuIt from severe mitral stenosis which is responsibIe for acute puImonary edema and from congestive heart faiIure of high degree invoIving the Iungs with bleeding therefrom. Pneumonia, puImonary infarction and tuberculosis are the most common pulmonary causes of hemoptysis. Pulmonary apop!e.y
Fever may be found with either heart or lung disease; but since puImonary infections are much more common than cardiac infections, fever is preponderantly a puImonary sign. AIthough rheumatic fever invoIving the heart, subacute bacterial endocarditis, acute myocardial infarction and acute pericarditis are a11 associated with fever, such temperature elevation is usuaIIy of low degree and these conditions are as a ruIe easy to diagnose. Tachycardia is common with both heart and pulmonary disease and therefore is in no way heIpfu1 in diagnosis except when the rate is very high (200, more or Iess), when some type of paroxysma tachycardia becomes quite obvious. An important manifestation of pulmonary embolism is tachycardia out of all proportion to the amount of fever; in such a case the differentiation from heart disease is not aIways easy. Tachypnea (increased respiratory rate) is infinitely more common with pulmonary disease than with heart disease. There is some increase, however, with congestive heart failure. One shouId remember too that breathing disorders, with or without tachypnea, are common in neurocircuIatory asthenia without disease of either heart or Iungs. Cyanosis is much more common with pulmonary disease than with heart disease and yet the deepest cyanosis is found in congenital defects of the heart and great vesseIs, as, in particuIar, the tetralogy of FalIot. In such cases the differentia1 diagnosis is easy. Rales in the lungs are much more common in

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puImonary disease than in heart disease ant1 as such they are most frequentIy due to infection, asthma, emphysema or bronchitis. Dependent raIes, especialIy at the extreme bases, fairIy common in cases with are, however, failure of the Ieft ventricle. As such they are a late sign of puImonary congestion, the symptom of dyspnea itself, whether paroxysmal or not, being much earlier. Dry raIes at the Iung bases should be carefuIIy distinguished from the moist rales of pulmonary edema. It should be stated here, however, that raIes of asthmatic nature are not infrequently found in patients with acute puImonary edema due to heart disease. In such cases the term cardiac asthmu has been applied. Dullness on percussion may be found at the Iung bases, especially at the right, due to hydrothorax, in right heart faiIure and in chronic constrictive pericarditis; but except for these conditions which are usuaIIy diagnosed with reIative ease, duIIness to percussion is a sign of pulmonary disease. One important cIue is that if dullness, with or without rales, is found at the left lung base and not at the right, the cause thereof should be sought in the Iungs (for example, pulmonary infarction or Ieft-sided pleuritis) and not in the heart except in rare cases where the left hydrothorax of congestive heart faiIure may be associated with obliteration of the right pleural cavity. A friction rub heard over the chest is almost invariabIy secondary to acute pleuritis. However, it may be heard over the heart itself due to pericarditis. When pericarditis is attended by pleuritis, the term pieuropericarditis is applied. The presence of loud heart murmurs indicates the presence of disease of the heart or great vessels, but frequentIy such disease is not responsibIe for symptoms or other signs. Many. patients with valvular heart disease live long Irves free of symptoms when there is only reIativeIy slight deformity of mitral or aortic valve, while some of the most serious cardiac patients with heart failure have verv little in the way of murmurs to be heard. Tks is particuIarIy true of patients who have serious coronary heart disease even with angina pectoris decubitus or acute myocardial infarction. Heart sounds are more important than heart murmurs. Diastolic gallop rhythm indicates dilatation of the left ventricIe when maxima1 at the apex and dilatation of the right ventricIe

Cardiac and PuImonary when located at the lower end of the sternum. It should aIways be regarded as an important cIue to the presence of serious heart disease. Accentuation of the puImonary second sound is, however, an occasiona finding in puImonary disease, as in instances of extensive puImonary fibrosis, massive puImonary emboIism or puImonary endarteritis obliterans with increased puImonary arteria1 pressure. Accentuation of the puImonary second sound is, of course, aIso a common finding in cases with mitral stenosis and left ventricuIar faiIure. Therefore, as a clue, it must be judged very carefuIIy. X-ray evidence is extremeIy helpful aIthough often onIy in a suppIementary way. The size of tbe beart can be best determined, of course, in this way. The smaIIer the heart, the Iess IikeIihood of heart disease or that the heart is responsibIe for such a symptom as dyspnea or cough. AbnormaIities of the great vesseIs are determined with exactness onIy by x-ray study, and many times it is onIy the x-ray fiIm that reveals maIignancy of the Iung or the scar of a puImonary infarct. CaIcification of the pericardium is an important cIue to chronic constrictive pericarditis. Pneumothorax and pleural and pericardia1 effusions are best determined by this technic. It is important in fIuoroscopy of the heart to make observations from different angIes, that is, in the obIique, IateraI and postero-anterior positions. The electrocardiogram is generaIIy normal in the presence of pulmonary disease. RareIy ex-

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tensive invoIvement of the Iungs, acute or chronic, can aIter the eIectrocardiogram as in the case of the rather typica acute car puImonaIe secondary to massive pulmonary emboIism. In the acute car puImonaIe, the eIectrocardiographic pattern is that of the appearance or accentuation of S waves in Iead I, Q waves in Iead III, and inversion of the T waves in Ieads III, aVF, Vs and Vs, and sometimes in Iead II. To be sure, the eIectrocardiogram may be norma aIso in serious heart disease, for exampIe, in coronary heart disease between attacks of angina pectoris, but advanced heart disease suficient to cause dyspnea, cough, hoarseness and hemoptysis can be considered to produce practicaIIy aIways an abnormal eIectrocardiogram. CONCLUSION

The cIinica1 differentiation of cardiac and puImonary disease is usuaIIy easy. Dyspnea, cough, hoarseness, hemoptysis, fever, tachypnea, cyanosis, raIes and percussion dullness are more commonIy found with Iung than with heart disease aIthough there are many exceptions. The symptoms and signs more commonIy found in heart disease incIude pain, tachycardia, heart murmurs and abnorma1 heart sounds. To supplement the analysis of symptoms and signs, x-ray and eIectrocardiographic studies are invaIuabIe and sometimes afford the conclusive cIues.

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