chemistry

Ischemic cardiomyopathy

Ischemic cardiomyopathy is a chemistry topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Ischemic cardiomyopathy rather than just read about it. In short: Ischemic cardiomyopathy is a type of cardiomyopathy caused by a narrowing of the coronary arteries which supply blood to the heart. Typically, patients with ischemic cardiomyopathy have a history of acute myocardial infarction, however, it may occur in patients with coronary artery disease, but without a past history of acute myocardial infarction.

Key takeaways

Ischemic cardiomyopathy belongs to chemistry; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Ischemic cardiomyopathy to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Ischemic cardiomyopathy from memory before moving on to harder problems.

Reference excerpt

Ischemic cardiomyopathy is a type of cardiomyopathy caused by a narrowing of the coronary arteries which supply blood to the heart. Typically, patients with ischemic cardiomyopathy have a history of acute myocardial infarction, however, it may occur in patients with coronary artery disease, but without a past history of acute myocardial infarction. This cardiomyopathy is one of the leading causes of sudden cardiac death. The adjective ischemic means characteristic of, or accompanied by, ischemia — local anemia due to mechanical obstruction of the blood supply.

Signs and symptoms Signs and symptoms of ischemic cardiomyopathy include sudden fatigue, shortness of breath, dizziness, and palpitations.

Cause Ischemic cardiomyopathy is the cause of more than 60% of all cases of systolic congestive heart failure in most countries of the world. A chest radiograph that demonstrates coronary artery calcification is a probable indication of ischemic cardiomyopathy. The following are causes of ischemic cardiomyopathy:

Diabetes Atherosclerosis Vasospasm Inflammation of arteries

Pathophysiology Ischemic cardiomyopathy is caused by too little blood flow and hence oxygen reaching the muscular layer of the heart due to a narrowing of coronary arteries in turn causing cell death. This can cause different levels of tissue injury and affect large and intermediate arteries alike.

Diagnosis Ischemic cardiomyopathy can be diagnosed via magnetic resonance imaging (MRI) protocol, imaging both global and regional function. Also the Look-Locker technique is used to identify diffuse fibrosis; it is therefore important to be able to determine the extent of the ischemic scar. Some argue that only left main- or proximal-left anterior descending artery disease is relevant to the diagnostic criteria for ischemic cardiomyopathy. Myocardial imaging usually demonstrates left ventricular dilation, severe ventricular dysfunction, and multiple infarctions. Signs include congestive heart failure, angina edema, weight gain and fainting, among others.

Management

Restoring adequate blood flow to the heart muscle in people with heart failure and significant coronary artery disease is strongly associated with improved survival, some research showing up to 75% survival rates over 5 years. A stem cell study indicated that using autologous cardiac stem cells as a regenerative approach for the human heart (after a heart attack) has great potential. American Heart Association practice guidelines recommend implantable cardioverter-defibrillator (ICD) use in those with ischemic cardiomyopathy (40 days post-MI) that are (NYHA) New York Heart Association functional class I. A LVEF measurement (simply called LVEF alone among cardiologists) of greater than (>) 30% is often used to differentiate primary from ischemic cardiomyopathy, and as a prognostic indicator. A 2004 study showed the patients in that study who underwent ventricular restoration as well as a coronary artery bypass achieved greater postoperative LVEF than with the latter surgery alone. Severe cases are treated with heart transplantation.

Prognosis One of the most important features differentiating ischemic cardiomyopathy from the other forms of cardiomyopathy is the shortened, or worsened all-cause mortality in patients with ischemic cardiomyopathy. According to several studies, coronary artery bypass graft surgery has a survival advantage over medical therapy (for ischemic cardiomyopathy) across varied follow-ups.

References

Further reading Likoff, Jessup Mariell, Chandler Sheryl L., Kay Harold R. (1987). "Clinical determinants of mortality in chronic congestive heart failure secondary to idiopathic dilated or to ischemic cardiomyopathy". The American Journal of Cardiology. 59 (6): 634–638. doi:10.1016/0002-9149(87)91183-0. PMID 3825904.{{cite journal}}: CS1 maint: multiple names: authors list (link) Carmeliet Peter; et al. (1999). "Impaired myocardial angiogenesis and ischemic cardiomyopathy in mice lacking the vascular endothelial growth factor isoforms VEGF164 and VEGF188". Nature Medicine. 5 (5): 495–502. doi:10.1038/8379. PMID 10229225. S2CID 7536458. Menasché Philippe; et al. (2008). "The myoblast autologous grafting in ischemic cardiomyopathy (MAGIC) trial first randomized Placebo-controlled study of myoblast transplantation". Circulation. 117 (9): 1189–1200. doi:10.1161/circulationaha.107.734103. PMID 18285565. Beltrami Carlo Alberto; et al. (1994). "Structural basis of end-stage failure in ischemic cardiomyopathy in humans". Circulation. 89 (1): 151–163. doi:10.1161/01.cir.89.1.151. PMID 8281642.

External links

Illustrations

Worked examples

Example 1 — a first encounter with Ischemic cardiomyopathy

Start with the simplest possible case. Write down what Ischemic cardiomyopathy claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In chemistry, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Ischemic cardiomyopathy before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Ischemic cardiomyopathy ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Ischemic cardiomyopathy

In research: Ischemic cardiomyopathy appears in chemistry research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Ischemic cardiomyopathy in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Ischemic cardiomyopathy is common in secondary-school and first-year university syllabi. It links to neighbouring topics Cardiomyopathy, so understanding it makes those chapters shorter.
In everyday life: Look for Ischemic cardiomyopathy outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

Ask Teacher Smith questions about this articleOpens your AI tutor with a question about “Ischemic cardiomyopathy” →

Affiliate

Preply — study more efficiently by working with a personal tutor. 50% off.

How to study Ischemic cardiomyopathy in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Ischemic cardiomyopathy means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Ischemic cardiomyopathy out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Ischemic cardiomyopathy in simple terms?

Why does Ischemic cardiomyopathy matter?

Because it connects several chemistry ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Ischemic cardiomyopathy?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Ischemic cardiomyopathy.