17.11
Angina I: introducción
Definición y síntomas: la angina (angina de pecho) es un dolor o malestar en el pecho causado por la isquemia miocárdica, que ocurre cuando el músculo…
La angina de pecho, o angina de pecho, es el dolor o malestar torácico causado por la isquemia miocárdica, en la que el músculo cardíaco recibe una cantidad insuficiente de sangre rica en oxígeno.
Por lo general, se siente como presionar, apretar o aplastar el pecho, a menudo irradiado a los hombros, los brazos, el cuello, la mandíbula o la espalda.
La causa principal de la angina de pecho es la aterosclerosis, en la que la acumulación de placa estrecha las arterias coronarias, reduciendo el suministro de sangre rica en oxígeno al músculo cardíaco.
Otros factores contribuyentes incluyen espasmos de las arterias coronarias, enfermedad microvascular y afecciones que aumentan la demanda de oxígeno del miocardio, como la hipertrofia ventricular izquierda o la taquicardia.
Los factores de riesgo que contribuyen a la angina de pecho incluyen hipertensión, hiperlipidemia, tabaquismo, diabetes, obesidad, estrés, inactividad física, mala dieta, edad avanzada y antecedentes familiares de enfermedad de las arterias coronarias.
La fisiopatología de la angina de pecho se debe a un desequilibrio entre el suministro y la demanda de oxígeno del músculo cardíaco.
Durante el aumento de la actividad física o el estrés, la demanda de oxígeno del corazón supera el suministro restringido debido al estrechamiento de las arterias coronarias, lo que provoca isquemia y dolor anginoso.
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Q1: What is angina and what does it feel like?
Angina, or angina pectoris, is chest pain or discomfort caused by myocardial ischemia, when the heart muscle receives insufficient oxygen-rich blood. It typically feels like pressing, squeezing, or crushing sensations in the chest and may radiate to the shoulders, arms, neck, jaw, or back.
Q2: What causes angina to develop?
The primary cause of angina is atherosclerosis, where plaque buildup narrows the coronary arteries, reducing oxygen-rich blood flow to the heart muscle. Contributing factors include coronary artery spasms, microvascular disease, and conditions that increase myocardial oxygen demand, such as left ventricular hypertrophy or tachycardia.
Q3: How does myocardial ischemia lead to anginal pain?
Angina results from an imbalance between the heart muscle's oxygen supply and demand. During increased physical activity or stress, the heart's demand for oxygen surpasses the restricted supply due to narrowed coronary arteries, leading to ischemia and anginal pain. This oxygen deficit triggers chest discomfort.
Q4: What physical and emotional factors trigger angina?
Physical activity such as walking, running, or climbing stairs increases the heart's workload and oxygen demand. Emotional stress can also increase heart rate and blood pressure, raising oxygen demand. Narrowed coronary arteries cannot deliver sufficient oxygen-rich blood to meet these increased demands, triggering angina.
Q5: What are the main risk factors for developing angina?
Risk factors include hypertension, hyperlipidemia, smoking, diabetes, obesity, stress, physical inactivity, poor diet, increasing age, and family history of coronary artery disease. These factors contribute to atherosclerosis and narrowing of coronary arteries, significantly increasing the risk of developing angina symptoms.
Q6: How do healthy coronary arteries differ from those affected by coronary artery disease?
In a healthy state, coronary arteries can dilate to increase blood flow and meet increased oxygen demand during physical activity or stress. In coronary artery disease, narrowed coronary arteries limit the ability to increase blood flow during increased oxygen demand, leading to ischemia and angina.
Q7: What role do microvascular disease and coronary artery spasms play in angina?
Microvascular disease affects small blood vessels in the heart, reducing blood flow and causing angina. Coronary artery spasms cause sudden, temporary narrowing of coronary arteries, also reducing blood flow and oxygen delivery. Both conditions contribute to myocardial ischemia and anginal symptoms in susceptible patients.