There can be little doubt but that the interstitial inflammation which gives rise to the valvular changes which allow aortic regurgitation is often excited by the violence with which the aortic valves are closed by the backward rush of blood on the aortic recoil during prolonged and violent physical exertion.
Thus, although rheumatism plays a very important part in its development, it is so far from being its sole cause that C. Hilton Fagge says that in at least half the cases of this form of valvular disease met with in London hospitals one fails to elicit a rheumatic history.
SYMPTOMS.—Rational Signs.—So long as hypertrophy of the left ventricle compensates for its dilatation, the individual will suffer little or no inconvenience, even though the regurgitation is extensive. When the regurgitant stream is a very small one there will also be little or no disturbance of the general health.
But the compensation is only maintained for a short time. When the equilibrium is lost the eccentric hypertrophy induces excessive heart-action during mental excitement or violent muscular effort. The action of the heart then becomes labored, and the patient becomes anxious, nervous, and fretful. Sufferers from aortic regurgitation are generally aware that exercise will augment all their uncomfortable symptoms. Their respirations are accelerated by moderate exercise, and are accompanied by cardiac palpitation. As the insufficiency increases attacks of headache and vertigo become more and more prolonged and severe; the patient complains of muscæ volitantes, dyspnoea, giddiness, and is compelled to sleep with his head elevated. Palpitation is now a constant symptom, and a visible carotid impulse is persistently present.
A comparatively frequent symptom of aortic regurgitation is a distinctly paroxysmal shooting or stabbing pain over the heart, in the left shoulder, or extending down the left arm. Sometimes this pain is accompanied by numbness and a peculiar whiteness of the skin along the line of the pain. In other cases the pain passes from the middle of the sternum to the right arm. This pain is increased by mental excitement and muscular exertion, and sometimes by over-distension of the stomach. In a few cases patients will complain of a sickening fluttering of the heart.
When the nutrition of the hypertrophied ventricular walls becomes markedly interfered with, or when insufficiency of the mitral valves occurs, the veins of the systemic circulation become overloaded, as is evidenced by cyanosis and dropsy; the dropsy appears first as oedema of the feet, and gradually extends upward until a condition of general anasarca is reached. The cyanosis is increased after slight exertion, and is accompanied by dyspnoea, carotid pulsation, and puffiness of the face.
In the advanced stages of the disease there is orthopnoea, sudden starting in sleep, angina pectoris, and in some cases albuminuria and enlargement and tenderness of the liver. Attacks of syncope at first occur only after active muscular exercise, but later they occur independently of it, and are extremely distressing. These patients are in danger of death at any moment, either during a state of the utmost calm or the most intense excitement; the danger is greater, however, during exertion.
The pulse is the most characteristic subjective symptom of this form of valvular lesion. It was first accurately described by Sir Dominick Corrigan,9 and it is frequently called Corrigan's pulse. He especially said that the disease was indicated by visible pulsation of the vessels of the head, neck, and upper extremities. On account of the elongation of the arteries during their pulsation, and their becoming distinctly flexuous, the pulse is frequently called the locomotive pulse. It is large and distinct, rapidly projected against the finger, and just as quickly the arterial tension sinks to its minimum and the impulse vanishes. It is sometimes accompanied by a vibrating jar, on account of which it is called the water-hammer, jerking, splashing, or collapsing pulse. Its characteristics are more apparent when the arm is raised above the head. Although slightly infrequent, quick, and jerking, it is always regular in rhythm; the radial impulse is felt a little after the apex-beat. Thus the pulse-wave of aortic regurgitation travels slowly along the arteries. This delay in the pulse is constant.
9 Edin. Med. and Surq. Journ., April, 1832.
As soon as the systemic circulation is overloaded from insufficiency of the heart or from secondary mitral insufficiency, the pulse becomes feeble and irregular upon the slightest exertion, and may intermit, but it is still of the same peculiar jerking character. The sphygmographic tracings of this pulse show a high upstroke and absence of the dicrotic wave.