Week 4 case study: congestive heart failure pathophysiology
A two-page case study analysis of a 76-year-old woman with decompensated congestive heart failure: the cardiovascular and cardiopulmonary processes behind her symptoms, the racial and ethnic variables that affect physiological functioning, and how those processes interact.
Editorial process
Last reviewed · August 7, 2026
What a 30-30-25 rubric does to a two-page paper
The rubric is printed in full underneath the scenario, and it reallocates the paper. Thirty per cent goes to describing the cardiovascular and cardiopulmonary processes, another thirty to explaining how those processes *interact*, and twenty-five to racial and ethnic variables. That last figure is the one worth staring at: a quarter of the mark rests on the bullet most submissions answer in two sentences on the way to the conclusion. Fifteen per cent is left for paragraph development, English writing standards and APA format. Two pages, three substantive sections weighted 30-30-25, and a purpose statement, introduction and conclusion the writing criterion explicitly requires. Allocate the space before drafting or the racial and ethnic section will be whatever is left over. A workable split is roughly half a page on each of the two pathophysiology sections, half a page on the interaction, and half a page on race and ethnicity.
The word *both* appears in the rubric twice, and it is doing real work. Cardiovascular and cardiopulmonary are two distinct chains, and a paper that follows only one of them looks complete while covering half the criterion. Backward failure into the systemic circulation is what produces this patient's peripheral oedema, abdominal swelling and weight gain; backward failure into the pulmonary circulation is what produces the shortness of breath and the need for two pillows. Write them as two named sequences with the sign each one accounts for, and the marker can tick both halves without inference. Every symptom the scenario lists should be attached to a mechanism by the end of that section, because the rubric asks you to describe the patient's symptoms and not heart failure in general. Naming the two chains in the section headings costs nothing and makes the coverage visible to a marker skimming for the word both.
Two details in the scenario are clinical findings rather than colour, and unused they are marks left on the table. Sleeping on two pillows to get enough air is orthopnea, and it is mechanistically specific: lying flat redistributes fluid from the legs and splanchnic bed into the thorax, raising pulmonary capillary pressure until breathing at rest becomes work. The diuretic non-adherence is the precipitant, and the patient's own reason — having to get up every couple of hours — is the adherence problem in one sentence. Name orthopnea and name the precipitant, because a paper that recites the symptoms without converting them into findings is describing the case rather than analysing it, which is the distinction the top rubric band is drawn on. The same applies to the abdominal swelling, which in this context is ascites rather than bloating and belongs to the systemic chain.
The interaction criterion is a separate thirty per cent and it is not a summary paragraph. What it wants is the loop: falling cardiac output is read by the kidney as hypovolaemia, the renin-angiotensin-aldosterone system and the sympathetic nervous system activate, sodium and water are retained, preload rises, and the failing ventricle is loaded further — so the compensation worsens the congestion it was recruited to fix. Once that loop is on the page, the pulmonary and systemic findings stop being two lists and become two outlets of one process, and the missed diuretic stops being a compliance anecdote and becomes the step that let the loop run unopposed. Write it as cause and effect rather than as a statement that the systems are related. It is also the paragraph that explains why the missed diuretic mattered so much, which is the question the scenario is really posing.
For racial and ethnic variables, the twenty-five per cent goes to specificity rather than acknowledgement. There is real evidence to work with: Black adults carry a higher incidence of heart failure and develop it younger, and a landmark trial found that adding isosorbide dinitrate and hydralazine to standard therapy reduced mortality in self-identified Black patients, which is why that combination sits in the guidelines as a race-specific recommendation. What lifts the section further is naming the caveat: race in these studies is self-identified and stands in for ancestry, access and structural exposure rather than functioning as a biological variable, which is exactly why race coefficients have been removed from kidney function estimates. That is a defensible, cited position rather than a gesture. Two well-sourced paragraphs will outscore a page of general statements here, because the rubric rewards accuracy and detail rather than length.
Finding in the scenario | The mechanism it belongs to | What to name it as |
|---|---|---|
Shortness of breath, two pillows | Pulmonary venous congestion | Orthopnea, from redistributed fluid when supine |
Peripheral oedema, abdominal swelling | Systemic venous congestion | Right-sided failure; ascites and dependent oedema |
Weight gain | Sodium and water retention | Fluid retention, the earliest measurable sign |
Stopped the diuretic | Loss of preload control | The precipitant, with the patient's stated reason |
History of congestive heart failure | Chronic compensated state decompensating | The baseline the exacerbation is measured from |
Likely learning objectives
Inferred from the brief — check these against your own rubric.
- 01Trace a patient's presenting signs back to distinct pathophysiologic mechanisms.
- 02Distinguish pulmonary from systemic consequences of ventricular failure.
- 03Explain neurohormonal compensation as a self-worsening loop rather than a repair.
- 04Discuss race and ethnicity in physiology with evidence and appropriate caution.
Read the full question
Review every instruction before using the planning guidance that follows.
Everything the case study analysis must contain
- 01A two-page case study analysis in APA format.
- 02At least three citations with three matching references.
- 03An explanation of the cardiovascular pathophysiologic processes behind the symptoms.
- 04An explanation of the cardiopulmonary pathophysiologic processes behind the symptoms.
- 05Racial and ethnic variables that may impact physiological functioning.
- 06An explanation of how these processes interact to affect this patient.
- 07A purpose statement, introduction and conclusion covering all required criteria.
From the missed diuretic to the neurohormonal loop
Frame the decompensation, not the diagnosis
A purpose statement naming this patient, her known heart failure, and the event that changed it.
The systemic chain
Backward failure into the venous circulation accounting for oedema, ascites and weight gain.
The pulmonary chain
Pulmonary venous congestion, dyspnoea and orthopnea, with the supine redistribution explained.
Racial and ethnic variables
Incidence and age of onset, the therapeutic evidence, and what race is standing in for.
The loop that ties them together
Reduced output, neurohormonal activation, retention, rising preload, worsening congestion.
Where the heart failure evidence actually lives
Recommended databases
- PubMed and PMC
- AHA and ACC guideline libraries
- NHLBI and NIH health topic pages
- HHS Office of Minority Health
Search sequence
- 1.Start from a current heart failure guideline, because it gives you the staging language and the race-specific recommendation in one citable place.
- 2.Find the trial behind that recommendation rather than citing the guideline for it, since the racial and ethnic criterion rewards primary evidence.
- 3.Look up incidence and age of onset by group, which is what turns an acknowledgement into a specific claim.
- 4.Check how the literature now frames race in physiological estimates, so the caveat you write is current rather than assumed.
A guideline, the trial behind it, and the disparity data
These are authoritative starting points, not a ready-made bibliography. A qualified reviewer must confirm that each source fits the assignment and supports the claim beside which it is cited.
Nothing here is cleared for citation until you have read it.
- 01
2022 AHA/ACC/HFSA Guideline for the Management of Heart Failure
Circulation, American Heart Association · 2022
The current staging and management framework, including the recommendation for isosorbide dinitrate with hydralazine in self-identified Black patients with reduced ejection fraction. Cite it for the clinical vocabulary and for locating the race-specific recommendation, then cite the trial itself for the evidence.
- 02
Combination of isosorbide dinitrate and hydralazine in blacks with heart failure
New England Journal of Medicine, via PubMed · 2004
The African-American Heart Failure Trial, stopped early for a mortality benefit. This is the primary evidence the racial and ethnic criterion needs — it lets you say what was measured, in whom, and with what effect, rather than asserting that responses differ between groups.
- 03
Heart Failure
National Heart, Lung, and Blood Institute, National Institutes of Health · 2024
A concise, citable account of left-sided and right-sided failure and the fluid retention that follows. Useful for checking that your two chains are described in standard terms before you attach this patient's specific findings to them.
- 04
Heart Disease and African Americans
Office of Minority Health, U.S. Department of Health and Human Services · 2024
Federal comparative data on cardiovascular disease burden by group. Use it for the incidence and mortality figures in the racial and ethnic section, and note that the source frames these as disparities in outcome rather than as differences in physiology, which is the distinction the strongest version of that section draws.
Before the case study analysis is submitted
Common mistakes
- Answering only the cardiovascular chain when the rubric says both, twice.
- Treating the interaction criterion as a summary rather than a mechanism worth thirty per cent.
- Giving racial and ethnic variables two sentences when they carry a quarter of the mark.
- Leaving the two pillows unnamed instead of identifying orthopnea and explaining it.
- Reporting the missed diuretic as non-compliance rather than as the precipitant.
- Describing heart failure in general instead of this patient's listed symptoms.
- Treating race as a biological variable with no mention of what it stands in for.
- Running past two pages, or omitting the conclusion the writing criterion requires.
Submission checklist
- Every symptom in the scenario is attached to a named mechanism.
- Both the pulmonary and the systemic congestion pathways appear explicitly.
- Orthopnea is named and explained by fluid redistribution when supine.
- The neurohormonal loop is written as cause and effect.
- The racial and ethnic section cites evidence rather than acknowledging the topic.
- The limits of race as a physiological variable are stated.
- Three or more citations match three or more references.
- The paper is two pages with a purpose statement, introduction and conclusion.
Use this guide to plan and review your own work. Follow your institution's rules and read our academic-integrity policy.
Written by
Aaron Bishop
MA, Education
assignment interpretation and research-methods coaching across disciplines
Aaron leads the EssayCrackers editorial desk. He works on how assignment briefs are read — what a rubric is actually asking for, and where students most often answer a different question than the one set.
Reviewed by
Dr. Nathan Cole
PhD, Rhetoric & Composition
Argumentation and thesis development
Nathan teaches first-year composition and directs a university writing center. He reviews EssayCrackers guides for argumentative soundness and citation accuracy.