{
  "abstract": "Background Dyspnoea and reduced exercise capacity are common features in hypertrophic cardiomyopathy (HCM) without left ventricular outflow tract (LVOT) obstruction, yet the haemodynamic mechanisms contributing to these symptoms are poorly described. This study aimed to characterise the haemodynamic response to exercise in patients with HCM without LVOT obstruction.Methods In this observational study, 121 subjects underwent right heart catheterisation with haemodynamic measurements during rest and supine incremental exercise: 59 patients with HCM without LVOT obstruction (58±12 years) and 62 healthy controls (49±17 years). Left ventricular (LV) filling pressure was assessed as pulmonary capillary wedge pressure (PCWP) and compared with diagnostic thresholds (rest: <15 mm Hg; exercise: <25 mm Hg). Group comparisons were performed using Student’s t-tests or Wilcoxon rank-sum tests, as appropriateResults At rest, patients had higher PCWP than controls (14±6 vs 9±2 mm Hg, p<0.001), while other haemodynamic parameters were similar. Already at mild exercise (25 W), patients showed elevated PCWP (27±7 vs 16±7 mm Hg, p<0.001), mean arterial pressure (100±18 vs 93±13 mm Hg, p=0.02), central venous pressure (12±6 vs 9±4 mm Hg, p<0.001) and mean pulmonary artery pressure (38±11 vs 26±8 mm Hg, p<0.001). At peak exercise, patients exhibited higher PCWP (32±8 vs 18±8 mm Hg, p<0.001), with lower cardiac index (6.4±1.8 vs 8.9±1.4 L/min/m², p<0.001), heart rate (114±21 vs 132±19 bpm, p<0.001) and arteriovenous oxygen difference (58±13 vs 64±6%, p=0.004). Peak exercise capacity (119±50 vs 149±40 W, p<0.001) and peak oxygen consumption (21±7 vs 35±8 mL/kg/min, p<0.001) were lower in patients. Abnormal PCWP was found in 68% of patients at mild exercise and 85% at peak, compared with 6% of controls at mild exercise and 24% at peak. PCWP at mild exercise was inversely correlated with peak oxygen consumption in patients (r=−0.61; 95% CI −0.7 to –0.4; p<0.001).Conclusion Patients with HCM without LVOT obstruction exhibited significant haemodynamic impairments during exercise. Abnormally elevated LV filling pressures were present even at low workloads and were correlated with reduced exercise capacity.",
  "authors": [
    {
      "affiliations": [
        "Cardiology, Bispebjerg Hospital, Copenhagen, Denmark"
      ],
      "name": "Helga Lillian Gudmundsdottir"
    },
    {
      "affiliations": [
        "Rigshospitalet, Kobenhavn, Denmark"
      ],
      "name": "Anna Axelsson Raja"
    },
    {
      "affiliations": [
        "Department of Cardiology, Rigshospitalet, Copenhagen, Denmark"
      ],
      "name": "Kasper Rossing"
    },
    {
      "affiliations": [
        "Cardiac, Bispebjerg Hospital, Kobenhavn, Denmark"
      ],
      "name": "Hanne Rasmusen"
    },
    {
      "affiliations": [
        "Cardiology, Sjællands Universitetshospital Roskilde, Roskilde, Denmark"
      ],
      "name": "Martin Snoer"
    },
    {
      "affiliations": [
        "Cardiology, Sjællands Universitetshospital Roskilde, Roskilde, Denmark"
      ],
      "name": "Lars Juul Andersen"
    },
    {
      "affiliations": [
        "Rigshospitalet, Kobenhavn, Denmark"
      ],
      "name": "Rikke Gottlieb"
    },
    {
      "affiliations": [
        "Rigshospitalet, Kobenhavn, Denmark"
      ],
      "name": "Alex Hørby Christensen"
    },
    {
      "affiliations": [
        "Department of Cardiology, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark"
      ],
      "name": "Henning Bundgaard"
    },
    {
      "affiliations": [
        "Herlev Hospital, Herlev, Denmark"
      ],
      "name": "Emil Wolsk"
    },
    {
      "affiliations": [
        "Cardiology, The University Hospital of Copenhagen, Copenhagen, Denmark"
      ],
      "name": "Christian Hassager"
    },
    {
      "affiliations": [
        "Department of Cardiology, Rigshospitalet, Copenhagen, Denmark"
      ],
      "name": "Finn Gustafsson"
    },
    {
      "affiliations": [
        "Department of Cardiology, Rigshospitalet, Copenhagen, Denmark",
        "Department of Cardiology, Bispebjerg Hospital, University of Copenhagen, Copenhagen, Denmark"
      ],
      "name": "Jens Jakob Thune"
    }
  ],
  "title": "Haemodynamic response to exercise in patients with hypertrophic cardiomyopathy without left ventricular outflow tract obstruction",
  "uid": "52b312c6-b352-5549-b19e-b1d8e92bbf3f"
}